# Description

Long division need not be the traumatic learning experience for 4th and 5th graders. This app (div2) does all the tedious multiplications and subtractions, leaving the student to learn and practice the basic long division skills of correctly guessing each digit of the quotient (answer) and testing whether it is correct. An additional benefit is the feedback that is provided after each quotient digit.

The long division exercises in this app are carried to 2 decimal places (hence the name div2). The user can specify the number of digits in the dividend (the number divided into) and the divisor. The divisor and dividend are randomly generated integers, so the user will never see any problem more than once. The random numbers of divisor and dividend may sometimes be such that the divisor goes evenly into the dividend, in which case the quotient may end in one, or more zeros.

If long division is done the old fashioned way (with pencil and paper) the student must struggle for each digit of the quotient, multiplying his guess by the divisor and then subtracting the product to test whether his/her guess is correct and to get the difference for determining the next quotient digit. If the student has guessed wrong, the whole step of multiplication and subtraction must be repeated over again. Worse still, the student may fail to detect the error of an incorrect guess, and the error will propagate through the rest of the solution. When the answer is scored (by the teacher, or someone) the hapless student must go back through the entire process to determine what went wrong.

This app will develop proficiency in the key long division skill of guessing the correct quotient digit. When the student is faced with a long division exam problem that must be done with pencil and paper, this proficiency will enable him/her to avoid wasting time multiplying incorrect quotient digits by the divisor, when the correct digit could be guessed to begin with. The instructions in this div2 app provide a set of rules that will guarantee that the user never requires more than 2 guesses for any quotient digit; half the time these rules will even give the correct guess on the first try. If you have a 4th or 5th grader struggling with long division, you will find this app to be a life-saver. Of course, the student who is having trouble with multiplication and subtraction should master these fundamental skills first (see my apps “multables” and “sub3”). Once multiplication and subtraction are mastered, this app will avoid the boring exercise of these skills while trying to master long division.

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# Reviews

Helpfulness

Newest

Rating

Helpfulness

All Versions

All Versions

Latest Version

3.4

86 total

5 38

4 14

3 3

2 5

1 26

nicole Snee

Would be great Would be great but it does the math for you, if you press a number it shows the number itequals up to....

User reviews

Simple But Good App My only request to developer is that they allow single digit for divisor and two digit for dividend. I am just teaching my daughter to learn long division. So, she is basically learning how to divide a number by 2, 3 etc. Since this app requires 2 digit divisor, she cannot use it. One more thing, give an option of integer division, i.e., where one does not have decimal numbers. But that said, this is my need. App does work great otherwise.

Great ap! Great fun ap. Should include decimals for the kids who are ready for the next step!

Review deleted

# Additional information

Updated

April 27, 2012

Size

425k

Installs

10,000 - 50,000

Current Version

2.0

Requires Android

1.6 and up

Content Rating

Low Maturity

Permissions

Report

Flag as inappropriate Offered By

Peter Gottlieb

Developer

# Similar

## Math (Division) Step By Step

Math Step By Step is an educational app that teaches long division step by step. Unlike most math apps, this app will guide you in an interactive way to do a multi-digit long division operation.

- No advertisements and requires no special permissions

- Lightweight (100k) app which means super fast download

- You can type your own numbers or let the app pick ones for you

- You can turn on or off the interactive mode. Interactive mode will force you to pick an answer to every step. If interactive mode is off then you only need to press the next button.

- You can turn on or off sounds.

## Division Training

With this app the learning of long division is a cinch!

In Step-by-Step mode, each single step of the division is explained and illustrated. The numbers involved in the current step are highlighted and explained.

Are you ready, then you can start the training mode. Here you resolve the division and can apply your newly acquired knowledge.

If you want to review a Division, then release mode is the right thing. Here you give a the Division and immediately get the result.

features:

- Solving mode

- Step-by-Step Mode

- Training mode

- Supports point numbers in dividends

- Supports divisor - Supports point values in the quotient

- Calculate with or without multiplication intermediate step

Please note that this version only supports 3-digit dividends! The full version can be purchased through to the in-app purchase!

See also Multiplication Training, Addition Training

## Division For Kids

A fantastic app for kids to learn and practice long division on their own. This app teaches kids simple division and long division with remainders. There are unlimited problems for children to practice and solve. This app is just perfect for kids who are learning division and also wish to test their knowledge of times tables upto 20 by solving division problems.

Two Modes: Each mode has 10 levels of difficulty.

1) Practice: Learn how to do long division with remainders starting with simple division. Unlimited problems in every level.

2) Test: Take division tests with 10 problems each in every level. Different problems every time you play.

How kids of grade 2 to 6 can benefit?

- Easily learn long division (with and without remainders) with step-by-step instructions (spoken aloud).

- Solve division problems like a game and try to cross every level of difficulty.

- Use the same app again and again to get new problems all the time.

- Easy problems for kids just learning division and difficult problems for kids who already know division.

- Kids will learn what the terms mean: quotient, remainder, dividend and divisor.

Why parents will love the app?

- It is fun to use and play. The child can learn and practice division all alone.

- Funny animations will keep the child hooked.

- Every step, problem and answer is spoken aloud to reinforce learning in a child.

Features

- Free to download and try out.

- Solutions available for practice problems

- 1st 2 levels free in both modes. Remaining 8 available via single in-app purchase.

- Just right for math of grades 2-6.

## Long Division

Learn how to long divide the fun way.

This app includes the following:

1. Instructional steps on how to long divide.

2. A math trick for long division.

3. Timed questions.

4. Practice Test.

5. The HMS Bringdown Song by DRitchie.

Always remember the rules to long division:

Divide!

Multiply!

Subtract!

And Bring it Down!

At Education Fun Online, we make education fun!

View other apps by us:

Long Division

Balancing Division 20 / ? = 8 / 2 either the free or paid version.

Divide Decimal

Distributive Property

Adding Subtracting Negative Integers

Reducing Fractions

Prime Numbers

Division Fun Free

Division Remainder

Addition Decimal Jade Theme

Multiplying Decimal Free

GCF

Fraction and Whole Number Multiplication Temple Theme

Adding Fractions with Like Denominators

Subtracting Fractions with Like Denominators

Multiplying Fractions

Dividing Fractions

Addition Decimal Ancient Temple Theme

Visit our website at www.educationfunonline.com to see what is coming up next!

This app includes the following:

1. Instructional steps on how to long divide.

2. A math trick for long division.

3. Timed questions.

4. Practice Test.

5. The HMS Bringdown Song by DRitchie.

Always remember the rules to long division:

Divide!

Multiply!

Subtract!

And Bring it Down!

At Education Fun Online, we make education fun!

View other apps by us:

Long Division

Balancing Division 20 / ? = 8 / 2 either the free or paid version.

Divide Decimal

Distributive Property

Adding Subtracting Negative Integers

Reducing Fractions

Prime Numbers

Division Fun Free

Division Remainder

Addition Decimal Jade Theme

Multiplying Decimal Free

GCF

Fraction and Whole Number Multiplication Temple Theme

Adding Fractions with Like Denominators

Subtracting Fractions with Like Denominators

Multiplying Fractions

Dividing Fractions

Addition Decimal Ancient Temple Theme

Visit our website at www.educationfunonline.com to see what is coming up next!

## Math practice(AD)

This application was originally for my daughter. When she entered the first grade, did not like math. Often a finger count addition and subtraction within 10. I have boughten a lot of exercise book for her, but costly and spend time to check right or wrong. So I made this app for her.

Functions:

(1)Addition and subtraction within 10 for children.

(2)Lower primary use two-digit add, subtract, multiply, and divide practice.

(3)Support four arithmetic operations

(4)There is the feature of Learning clock.

If you have any advice or trouble about this app, please contect us.

std.bee@gmail.com

## Longhand Math

Do long addition, long subtraction, long multiplication and long division the way you learned in school using pencil and paper!

Add: see all of the carrying.

Subtract: see all of the borrowing.

Multiply: see all of the intermediate additions.

Divide: see all of the multiplication and subtraction steps.

Divisions can be performed with a decimal result or a remainder result.

Please note that Longhand Math simply draws the whole result at one time; it does not go step by step and it does not ask the user for what they think is the next step or anything of that nature. It does not attempt to teach you how to do long math or long arithmetic; it is simply a no-nonsense to-the-point application that directly gives you your answer with the necessary steps.

Great for checking homework!

## 2DigitAdditionByWriting

At first I Made a multiplication exercises app, but for computation by writing at the two-digit addition, my son has so many problems. So I made an app that can practice the calculation by writing of the addition.

There are two parts addition and addition carry, and provided the practice of 146 set. There is 20 die in one set, one set one day.

I think it provides a set portion of the 96 have carry in particular, to be able to practice carefully.

There is also an alarm and statistics function.

There are two parts addition and addition carry, and provided the practice of 146 set. There is 20 die in one set, one set one day.

I think it provides a set portion of the 96 have carry in particular, to be able to practice carefully.

There is also an alarm and statistics function.

## 2DigitSubtractionByWriting

At first I Made a multiplication exercises app, but for computation by writing at the two-digit subtraction, my son has so many problems. So I made an app that can practice the calculation by writing of the subtraction.

There are two parts subtraction and subtraction carry, and provided the practice of 150 set. There is 20 die in one set, one set one day.

I think it provides a set portion of the 100 have carry in particular, to be able to practice carefully.

There is also an alarm and statistics function.

There are two parts subtraction and subtraction carry, and provided the practice of 150 set. There is 20 die in one set, one set one day.

I think it provides a set portion of the 100 have carry in particular, to be able to practice carefully.

There is also an alarm and statistics function.

## 脳トレのための筆算練習帳

足し算、引き算、掛け算、割り算の筆算を練習するためのアプリ。

デフォルトは脳トレ（脳の前頭前野を活性化するため）の学習モードに設定してあり、大人から高齢者までが脳トレ（認知症の予防など）のために使用することができるが、設定を変更すれば小学4年生レベルの整数（自然数）の筆算練習にも使用できる。

問題と白板（ホワイト・ボード）を並べて表示することもでき、画面上の白板に手書きで筆算練習をできるようにしてあるが、あくまで手元に筆記用具がないときの便宜用であり、脳トレのためには紙の上にペンで手書きする方が望ましい（画面の上に手書きするより紙の上にペンで手書きする方が前頭前野が活性化しやすい*）。

[当アプリの特徴]

・ボタンのタップだけで「問題の表示」→「解答の表示」→「正解／不正解の選択」→「次の問題へ」と操作を繰り返し、あらかじめ設定しておいた問題数（ノルマ）に達した段階で成績を自動記録。

・過去の成績は「オプション」メニューから「成績記録の表示」を選ぶことによりいつでも表示可能。

・計算の対象は整数（自然数）のみ。（要望があれば今後のバージョンアップで小数点も扱う。）

・脳トレの学習モードと小学4年生レベルの学習モードは簡単に切り替えられる。

・デフォルトの脳トレの学習モードでは足し算・引き算・掛け算の問題が無作為に出題され、計算対象は1桁のみ**（ただし引き算だけは「2桁引く1桁」の問題も含まれる）となる。また、問題数（ノルマ）は100に自動設定される。（これらが前頭前野の活性化に一番効果的）

・小学4年生レベルの学習モードでは、足し算（4桁＋4桁）・引き算（4桁－4桁）・掛け算（3桁×3桁）・割り算（3桁÷2桁）の問題が無作為に出題され、問題数（ノルマ）は20に自動設定される。

・オプションの詳細設定により、足し算・引き算・掛け算・割り算の選択や桁数は細かく設定変更できる。また、問題数（ノルマ）も自由に設定変更できる。

・割り算は「余りなし問題」だけに設定変更することもできる。

・割り算の余りは旧式の表記（「・・・」のあとに余りを書く表記）も設定可能（年配者向け）。

・成績記録は不要ならばいつでも抹消できる。

・前頭前野の活性化のためには、できるだけ速く計算することが必要なので、成績記録には所要時間も自動記録し、あとで（「成績記録の表示」で）リストして所要時間の進歩も確認できるようにしている。

・操作方法がわからないときは、「操作案内メッセージを表示する」ラジオボタンを選択すると、操作方法を案内する縦書きメッセージが表示される。あるいは、画面の左側をタップするとトースト形式のメッセージで操作方法が案内される。

・初期画面の下のほうの邪魔にならない位置にバナー広告が表示される。

(注*: 前頭前野を活性化させるためには暗算ではなく、ちゃんと手書きで計算する必要があります。簡単に暗算できてしまう人も、できるだけ手書きしましょう。しかも、できるだけ素早く行うことが肝心です。正確に解答することも大切ですが、それ以上に解答の所要時間を縮める努力をしましょう。)

(注**: 桁数の少ない計算のほうが前頭前野が活性化しやすいという性質があります。)

## TimzTables (Free)

Voice Interactive - Animated - Audio - Multiplication Tables (Times Tables) - 17 Languages (English, Français, Deutsch, हिन्दी, Italiano, 普通话, Punjabi, 日本語, Português, 한국, Pусский, Español, العربية, Gujarati, فارسی, tiếng Việt, Bengali).

TimzTables allow children to learn Times Tables (Multiplication Tables) by rote - that is, the memorization of Times Tables through repetition.This is a time proven method, that embeds Multiplication Tables in a child mind at an early age. It's akin to training in sports, the neural pathways in the brain are reinforced, and with repetition become stronger, making easier to recall and harder to forget.

TimzTables is a great way for kids to learn Times Tables (Multiplication Tables), numbers, and phrase in another language.

TimzTables allows for testing of a child knowledge of Times Tables (Multiplication Tables) through voice input. Voice recognition is available in most of the languages in which TimzTables is offered. If your language is not supported, a child could say the answer in English or choose another language. WiFi or LTE is needed for voice recognition in all languages, except in English which also allows for Airplane Mode operation.

So why do to the trouble of memorizing Times Tables (Multiplication Tables), you may ask? Here are several reasons why the Times Tables (Multiplication Tables) are important:

1. So you can calculate your change when you buy stuff and not get robbed.

2. For everyday calculations, recalling Times Tables (Multiplication Tables) from memory is much faster than using a calculator.

3. Times Tables (Multiplication Tables) are a bench press for the brain!

4. After a 30 year absence, the British Government made it mandatory in 2012 that kids learn all 12 Times Tables (Multiplication Tables) by age 9 -- Knowing Times Tables is that important! Kids, if anyone tells you that Times Tables and Long Division are not important, ignore them.

5. Kids who know Times Tables (Multiplication Tables) have a definite advantage in school ... Long Division and High School Math become much easier.

6.Parents, if you hire a Math Tutor for your child, make sure that Tutor knows Times Tables (Multiplication Tables) and Long Division ... Many DON’T!

7.Many High School Math problems are easily solved with Times Tables (Multiplication Tables).

For example,

In the quadratic equation below, find a and b:

X2 + 19x + 84 = (x + a) (x + b)

Solution:

The following is always true:

a x b must equal to 84.

a + b must equal to 19.

And, from Times Tables (Multiplication Tables), we know...

7 x 12 = 84

and

7 + 12 = 19,

Therefore, a must be 7 and b must be 12.

It’s that easy!

Final Answer: X2 + 19x + 84 = (x + 7) (x + 12)

Quadratics like these are found right through High School and University.

8. Most of the professions below pay well. All require knowledge of Times Tables (Multiplication Tables) and Long Division:

App Developer, Animators, Accountants and Auditors, Actuaries, Aircraft Pilots, Air Traffic Controllers, Architects, Bank Tellers, Carpenters, Chemists, Computer Programmers, Cost Estimators, Dentists, Doctors, Draftsmen, Economists, Engineering Technicians, Engineers, Environmental Consultants, Fashion Designers, Financial Analysts, Forensic Analysts, Geographers, Geologists, Interior Designers, Machinists, Math-Science-or-Technology Teachers, Mathematicians, Management Consultants, Members of the Military, Meteorologists, Nuclear Physicists, Optometrists, Pharmacists, Physicists and Astronomers, Real Estate Agents, Statisticians, Stock Brokers, Technical Writers, Tool and Die Makers (Numerical Control), Underwriters, Urban Planners.

## Maths Multiplication Factors

Hardcore straight-forward learning method of Multiplication through TABLES and FACTORS (includes prime factors too).

Presents you with a list of tables (1 to 99) to choose from.

Move through the tables by casually swiping the screen to the left or right. Click on any line in the table to load the factors of all the numbers in the line (makes it easy to remember)

Presents you with a list of tables (1 to 99) to choose from.

Move through the tables by casually swiping the screen to the left or right. Click on any line in the table to load the factors of all the numbers in the line (makes it easy to remember)

Choose 'Endless Table' mode to continuously keep increasing the table range till 999.

No more need to remember an infinite number of tricks to multiply two numbers. Just practice with this and you'll remember them forever.

This version is for devices running Android Version >= 2.1

If your device run's on Android Ver < 2.1 then search for 'Maths Multiplication Legacy' or 'com.felix.legacy.multiplication' in the Android Market.

####Features####

1. Open “Multiplication Tables” from the home screen to view the tables of a number from 1 to 20 (Try ‘Endless Mode’ in Settings). Click on any item to open it's quick factor info. Long click for loading the table, factors or Grid of all the numbers present in the table item.

2. Open Numbers Grid to load a grid of numbers. The grid is an Endless list of numbers. Clicking on any number will load it’s factors. Long click any number below 100 to load it’s table.

3. Open “Load Table” and enter a number (1 to 99) to load it’s Multiplication Table. Click on any item to open it's factor info.

4. Open “Find Factors” and enter a number (2 to 999999) to load it’s Prime Factors and All Factors. You can further search by clicking on the Options menu and selecting “Find Factors”

Open Squares (x^2), Cubes (x^3) and Powers (x^y) from x=2 to 100.

5. Long Click on table's in either Tables view or Factor's View to select numbers to load their tables, factors (again) or Grid.

Press Volume Up/Down to load prev/next item.

### Options Menu ###

Previous: Loads the Previous Multiplication Table

Next: Loads the Next Multiplication Table

Open Table..: Opens the Multiplication Table of the specified number (1-99)

Reset: Resets/Refreshes the current table to it’s default preferences.

Settings: Opens the Preferences for Multiplication Table View.

### Table Preferences ###

Limited Table Mode: Tables load from a specified from value to a specified to value (which can be set in the settings).

eg:

2 x 1(From) = 2 to

2 x 20(To) = 40

Endless Table Mode: Tables Load Continuously as you keep on scrolling from a specified value to 999.

eg:

2 x 1(From) = 2 to

2 x 999(Loads Dynamically) = 1998

### Table Default Settings ###

Text Size: Set the text size for all the text in the Multiplication Table View. Minimum size required for visibility purposes is 10.

Multiply From: The default beginning From value to start multiplying from.

Multiply Upto: Default ending To number to end the multiplication at.

Table No: This is the default Table No. that the application should load when it is first started. The application remembers the last visited Table and loads it by default every time.

Text Alignment: Specifies the alignment of the Table’s text (Left, Center, Right, etc)

### Color Preferences ###

Use Theme: The Theme that should be applied to the table’s and popup’s. Four theme’s are provided by default – Blue, Red, Pink and White.

Disable Theme: Disable’s the theme mode. No background effects are applied when this is selected. But when the theme’s are enabled, the option to select the text-color is available.

Table Text Color: The Color of the numbers that appear in the multiplication table view – Black, Blue, Cyan, Dark Gray, etc.

Text Background Color: The background color of the Table text. This is disabled if the theme mode is enabled.

Separator Color: The color of the Separator lines and the Table List’s background. This is also disabled if the theme mode is enabled.

A great math workout tool for you.

Keywords: Maths, Multiplication, Factors, Tables, Learn, Algrebra, Workout, Multiples, Factorization, Addition, Subtraction, Division.

# More from developer

## sub3

Most 2nd and 3rd graders struggle with subtraction problems that require borrowing. Having to strike-through numbers and then stack new numbers above them is a confusing process that leads to frustration and under achievement. Here is the answer: let the student step through a prompted sequence and be checked as he/she goes. Let the student concentrate on the essential arithmetic without having to worry about doing neat strike-through's and lining up columns of new numbers. Your child/student will appreciate the neat tableau that is generated as he/she follows the prompts and answers the questions. The prompts consist of either a yes/no question regarding whether a particular column needs to borrow or question marks where the new numbers should be in the normal borrowing tableau (“?” if a single digit answer is expected, and “??” if a 2 digit answer is expected). The question marks are automatically replaced by numbers entered from the virtual numeric keypad occupying the lower part of the screen. If the student accidentally presses the wrong numeric key, it can be erased by the “del” key and re-entered. All numeric entries are committed by tapping the “done” virtual key. If the student commits an incorrect answer, the error count is incremented, and he/she is instructed to try again. The student cannot proceed to the next step until the correct answer (numeric value or yes/no).

When the problem is complete both the student and the teacher/parent can see if any errors were made (and corrected) along the way before arriving at the final answer. Doing a sequence of exercises without errors will demonstrate that the skill has been mastered.

Most arithmetic programs follow the “electronic flashcard” paradigm: just present the problems for the student to work and score the response when the student is finished. This leaves the student to struggle through the solution with pencil and paper. If the student finally enters an incorrect answer, and the computer tells him so, the student has no idea what went wrong. In contrast sub3 provides prompts that present the student with a sequence of challenges and immediate feedback after each step. A tedious exercise is turned into a fascinating game. Another advantage of sub3 is that the numbers for each problem are generated randomly so the student will never see the same problem twice.

The extensive instructions included with this app provide comprehensive descriptions of all the steps involved in subtraction with borrowing, which will be a great help for the parent who needs to supplement what the student has learned in the classroom. This initial, free, version of the program uses only 3 digit numbers (hence the name sub3), which should provide sufficient problem variety to ensure the development of excellent student skills. If several thousand people install the free app, I will provide an extended version to allow the user to choose a larger number of digits, and charge a few dollars.

## Solvequad

Here is a drill program that will improve the essential skills for any intermediate algebra student. This is an exercise in the factoring of quadratic expressions. Such an expression can be written as the product of 2 factors, each factor consisting of 2 terms: an x to the first power term and a constant term. In the Solvequad app these 4 coefficients are randomly chosen integers from 1 to 6.

The top/first line of the Solvequad screen presents the quadratic expression. The second line shows the skeletons of the 2 factors that produce this expression, with 4 blank gray buttons for the 4 unknown coefficients. The user enters the numbers for these coefficients using the virtual keypad. This keypad has only the needed digits, 1 – 6, a minus sign, a delete key and a done key. The small number of keys means that the individual keys can be nice and large, minimizing entry errors. Accidental errors that do occur can be quickly corrected with the delete key. The selection of the coefficients to enter is made either by tapping the appropriate gray button, or by tabbing through the 4 buttons.

The third line on the screen shows the quadratic expression calculated as the coefficients are entered. This automatic calculation saves the user the trouble, so that he/she can concentrate on deciding which values to enter for the coefficients. After all 4 coefficients have been entered the student can compare the calculated quadratic expression in the third line with the problem quadratic expression in the first line. Any discrepancies can be corrected by re-entering the any of the coefficients of the factors. (second line of the screen). The done key is tapped when the user is satisfied that the first and third line quadratic expressions are the same. If the expressions are not the same the user is charged with an error and is told to re-enter the factor coefficients until the correct quadratic expression is calculated. This policy makes if easy for the student to avoid errors. The real strategy is to finish quickly by doing the correct coefficient calculation mentally so that there is no need to re-enter. The current version of the program does not track the completion time, but that capability can be added if there is sufficient interest.

Factoring a quadratic expression leads directly to solving for the 2 roots of the equation made by setting the quadratic expression equal to zero (values of x that make the quadratic expression equal to zero), hence the app name: Solvequad. The quadratic expression will equal zero when either of the 2 factors equals zero, so the roots of the quadratic expression are the 2 values of x that will make either of the 2 factors equal to zero. To the student of intermediate algebra this last step (solving a simple linear equation in one unknown) is trivial; it is left out of this app to limit the app to one process/algorithm and to avoid boring the user with trivia.

## linear1

This app raises the algebra drill program to a whole new level. Instead of simply presenting the problem and leaving the student to work out the steps on paper, the student is lead through a succession of steps, with instant feedback at each step. In this manner the student can quickly identify and understand his/her errors. The student also avoids the tedium of writing out the intermediate equations corresponding to these steps and worrying about keeping the equations neat and having enough space on the paper. The instructions with this app also provide a nice tutorial on the subject.

This app deals with a simple type of algebra problem: one linear equation in one unknown. This type of equation is a first step in the solution of many word problems; it is also fundamental to learning the more advanced concepts of algebra. The program begins with a single equation with all the constants generated randomly (so that the student is unlikely to ever see the same problem twice). The form of the equation is fairly general, having one variable term (x multiplied by a constant) and one constant term on each side of the equation. The student is lead through a 3 step process to solve the equation, to obtain a single numeric value for the unknown variable, x. The steps are structured so that the student's entry at each step can be checked, and instant feedback is provided.

Each step is completed by entering a number using a virtual numeric keypad with large buttons to minimize error. If the number entered is correct the student progresses to the next step. If the number entered is wrong the student is notified and prompted to re-enter the number until it is correct.

The arithmetic for each of the 3 steps (subtraction, or dividing by 2, 4, or 5 to get decimal answers) is simple enough to be performed mentally, without resort to pencil and paper. Hence drill with this app will have the added benefit of increasing proficiency in the simple mental arithmetic.

The program usually runs through a specified number of problems, and the number of errors is tallied after the last problem. This is most useful in a teacher-student setting, where the number of errors at the end of the sequence can be used to evaluate the student's progress, sparing the teacher the tedium of grading the problems individually. The number of problems in the sequence can be specified by the user.

## FlashDigits

Here is a game that tests your visual reflex, your short-term memory, and your ability to resolve a rapid sequence of images. Randomly selected digits (0-9) are flashed briefly on the screen in a rapid sequence. You are then asked to recall the sequence and enter the numbers using a virtual keypad. If correct, you can proceed to the next round with a shorter display time for each digit. The object is to get to as short a display time as possible. The challenge is to train your brain to make the persistence time of each digit image as short as possible, so that images don't interfere with each other.

If your answer is wrong you get a comment on your capabilities, as demonstrated by your performance. You can try again to improve, starting with the original, longer display time. The instructions give some hints that may be useful in this regard.

The can select the number of digits in the sequence from 2 through 6, the initial display time from 0.3 to 0.7 seconds, and the fraction by which the display time is reduced after a successful round from 0.2 to 0.4.

## factorit

Here is the best tool for improving a student's skill at factoring. The app presents a target number to be factored, and the student responds by entering a prime factor (2, 3, 5, 7, 11) of that number. For example, if the initial target number is 210 (2*3*5*7), and the user enters 5, the app will do the division and respond with the partial factoring 42*5, and the user is prompted to enter a factor of the new target, 42. The process repeats until the original number (210 in this case) is completely factored. If, at any step, the user enters a number that is not a prime factor of the target number, an error is charged and the user is prompted to re-enter a correct factor. When the factoring is complete the app displays the number of errors. This automatic, real-time, scoring saves the teacher, or tutor, the trouble of correcting the exercises, and provides the student with immediate feedback. A very efficient process for all concerned.

The app can be set up to run a specified number of problems, and will keep a tally of the number of errors. This automatic scoring saves the teacher, or tutor, a lot of trouble. The other adjustable parameters are the number of factors in the original problem (2 through 5) and the maximum prime factor (5, 7, 11, or 13). The instructions give all the essential tips to help the student find a factor correctly the first time (avoiding being charged with an error) without the bother of a short division exercise to test it. Since the app does all the division, the student can concentrate on getting the factors. This will sharpen his/her skills, even in the midst of all the distractions that modern youth is subject to.

## divisionfun

Here is a division drill that will develop skills in both basic division and mental arithmetic. To make the drill-pill easier to take, the program is simple enough to do while watching children's TV. The student can begin with division problems having no remainders, only one digit quotients. If the student enters the wrong number he gets charged with an error.

Division with remainder presents slightly more challenges. The answer is entered in a 2 step process: first the quotient; when that is correct the remainder is entered. The number of cases and problem difficulty can be selected from a setup menu. After completing the selected number of cases, there is a display of the number correct and the number of errors to show the teacher of parent.

## div1

Here is a division drill that will develop skills in both basic division and mental arithmetic. Yet it's simple enough to do while watching children's TV.

The student can begin with no remainders: dividing integers from 3 to 9 (called divisors) into a dividend which has been calculated so that the division is even. After the student enters the answer (a single digit in the simplest version) it is scored and, if correct, he/she progresses to the next problem. If incorrect, the student is prompted to re-enter the correct answer. As each problem is completed the number of errors is tallied. At the end of the sequence the student has evidence of his/her progress that can be shown to the teacher/parent.

Division with remainder presents slightly more challenges. The answer is entered in a 2 step process: first the quotient; when that is correct the remainder is entered. The number of cases and problem difficulty can be selected from a setup menu. The problems are built from factor numbers selected at random, so the student is unlikely to encounter the same problem twice in a sequence, and almost never for problems with remainder.

The beginning student/user is expected to use pencil and paper for calculating remainders (particularly the first few times the app is used). However, he/she should be encouraged to do without pencil and paper as soon as comfortable. Calculating the remainder without resorting to pencil and paper provides a nice drill in simple mental arithmetic.

## linear2

Here is a painless way for the algebra student to develop proficiency in solving simultaneous linear equations. Here is a drill program that leads the student through 8 steps to solve 2 simultaneous linear equations with 2 unknowns. These 8 steps would be a tedious exercise with pencil and paper. Even worse, a single error at one of the steps would not be detected until the problem was finished, and the student would be left with the unpleasant exercise of re-doing the whole problem in order to find out what went wrong. This app (Linear2) will check each of the 8 intermediate steps and provide immediate feedback to the student. The values of the 2 unknowns and the 4 coefficients in the equations are randomly generated so that there are several hundred thousand possible combinations, and it is extremely unlikely that the student will see the same problem twice.

This new version (2.0) is a little more user friendly and prevents crashes from faulty user input.

## multtables

Here is the answer to those tiresome multiplication table exercises with your child. This Android app will flash a sequence of multiplication table questions, and you child will enter the answers to each using a virtual numeric keypad with nice large keys. The virtual keypad even has a “delete” key so that hitting the wrong button can be corrected before getting charged with a wrong answer. Each question will be selected randomly by the program. You (or your child) can select the total number of questions for the sequence before the start. Since a given sequence will have no repeated questions, there can be up to 28 different questions in the sequence. Another unique feature that distinguishes this app from the countless other flash-card type apps: after each incorrect answer the subject is forced to view the multiplication table so that he/she is forced to become familiar with the table and its relationships.

The number of correct and incorrect answers is tallied and displayed at the end of the session so that you can verify your child’s progress. In constructing the multiplication table questions the numbers 10 and 2 are omitted because they make the multiplication question too easy, and the child would be annoyed at having to waste time answering trivial questions.

## myformulas

This app is for anyone who has to calculate formulas: high school and college students in science, engineering, or business courses, as well as teachers or practitioners in any of these fields who need to get quick results when they are not near their computer. It will handle a wider variety of formulas than most hand-held calculators, particularly formulas for which you want to use named variables and change their values frequently. Not only is this app easier to use than most hand-held calculators (being able to use parentheses rather than the tricky reverse Polish format required by most HP machines), it is also easier to use than the formula editing feature of a spreadsheet. Entering formulas is a snap: all you have to do is type in characters as you would with a text editor; the program parser will identify any variables and set up a screen for you to enter their values. Alphabetic and numeric characters are entered on different keypads in order to provide you with larger keys to minimize data entry errors. Close integration makes switching between these keypads very fast and easy.

Once you have entered a formula structure, and the initial values for any variables it might have, you can name and store it for future use. You can scroll through the list of stored formulas and recognize by name or formula structure any that you want to re-use.

Business or financial users will find this app a good complement to the calc_formulas app (by the same author and available for free), which allows the user to select from a list of 27 frequently used financial formulas, but does not have the capability to create new formulas.

The only deficiency in “myformulas” is the absence of a built-in function library. If more than 1000 people will pay $2.50 for this version, I will produce a slightly more expensive version with a function library more complete than any spreadsheet.

## calc_formulas

Here is an app that can calculate 27 different formulas useful in financial transactions. This latest version of the app has added a numeric keypad (with nice large keys) for data entry, as an alternative to the 2 modes of data entry in the original version: (1) dragging your finger up or down the screen to increase or decrease the default value of an input parameter, (2) tapping on a blank space on the screen for the same purpose.

The 27 formulas can be divided into 5 categories: (1) interest functions which range from simple interest to mortgage payments to bond price to yield a specified interest when the stated rate of the bond (frequently called coupon rate) is specified, (2) notes and payments, (3) profit and loss (including internal rate of return), (4) inventory valuation, (5) depreciation.

The 27 formulas can be divided into 5 categories: (1) interest functions which range from simple interest to mortgage payments to bond price to yield a specified interest when the stated rate of the bond (frequently called coupon rate) is specified, (2) notes and payments, (3) profit and loss (including internal rate of return), (4) inventory valuation, (5) depreciation.

This app can only calculate the 27 specified formulas, but it is free. If several thousand people download it and give me favorable reviews, I will do an enhanced app (for which I will charge a few dollars) that will allow the user to specify his/her own formulas, which may incorporate one or more of these 27 hard coded formulas.

## quickview

Can you read a number that's flashed on the screen for only a few milliseconds? This game will start with a few hundred milliseconds and reduce the duration until you can no longer enter the number correctly. You can select the number of digits; 3 is very easy; 5 is very hard. Practice and notice the improvement. Find the time of day when our visual acuity and ability to concentrate is highest. Test your skill against friends and family; it will be rewarding activity for ages 8 and up. This initial version is free, but not very slick; if it generates sufficient interest, I will add many features (such as keeping statistics on scores and for different players) and charge a few dollars.