Tuesday 29 January 2013

All iDevBooks subtraction apps information and a giveaway


Today our Developer of the Week iDevBooks are featuring their subtraction apps. Again these are designed to be used as a teaching tool not a game and are very effective...
Four of the subtraction apps below were in the REMLE project study. All 17 iDevBooks maths apps in the study were found to be very effective in teaching special needs children. Official results will be out later this year.
We have a giveaway running for one of the apps Column subtraction. Enter via the Rafflecopter below.



First app today is Column Subtraction

This app is designed for both iPhone and iPad
  • $3.99
  • Category: Education
  • Updated: Nov 20, 2012
  • Version: 2.3
  • Size: 18.8 MB
  • Language: English
  • Seller: Esa Helttula
Requirements: Compatible with iPhone, iPod touch, and iPad. Requires iOS 4.3 or later. This app is optimized for iPhone 5.
To purchase the app now please use the following link iTunes

Description

This math app can be used to teach and study the column subtraction method. The app is easy to use and it has an intuitive interactive interface with customizable colors and other settings. The user can solve random or custom subtraction problems with small and large numbers. The number of digits in the numbers can be set.

The column subtraction method is also known as columnar subtraction, long subtraction or longhand subtraction. 
We have 7 copies to give away. Please enter via the Rafflecopter below

a Rafflecopter giveaway


Second app today is Trade-First Subtraction

This app is designed for both iPhone and iPad
  • $3.99
  • Category: Education
  • Updated: Oct 14, 2012
  • Version: 2.1
  • Size: 1.6 MB
  • Languages: English, French
  • Seller: Esa Helttula
Requirements: Compatible with iPhone, iPod touch, and iPad. Requires iOS 4.3 or later. This app is optimized for iPhone 5.


Description

This app can be used to teach and study the trade-first subtraction method. The app is easy to use and it has an intuitive interactive interface with customizable colors and other settings. The user can solve random subtraction problems with small and large numbers. The number of digits in the numbers can be set. 
To purchase the app now please use the following link iTunes


Third app today is Partial Differences Subtraction
This app is designed for both iPhone and iPad
  • $3.99
  • Category: Education
  • Updated: Feb 07, 2012
  • Version: 2.1
  • Size: 0.6 MB
  • Language: English
  • Seller: Esa Helttula
Requirements: Compatible with iPhone, iPod touch, and iPad. Requires iOS 3.2 or later
To purchase the app now please use the following link iTunes 

Description

This math app can be used to teach and study the partial differences subtraction method. The app is easy to use and it has an intuitive interactive interface with customizable colors and other settings. The user can solve random subtraction problems. The number of digits in the numbers can be set.

Fourth app today is Equal Addition Subtraction
This app is designed for both iPhone and iPad
  • $3.99
  • Category: Education
  • Released: Dec 23, 2012
  • Version: 1.0
  • Size: 1.5 MB
  • Language: English
  • Seller: Esa Helttula
Requirements: Compatible with iPhone, iPod touch, and iPad. Requires iOS 4.3 or later. This app is optimized for iPhone 5.
To purchase the app now please use the following link iTunes

Description

This math app can be used to teach and study the equal addition subtraction method. The user can solve random or custom subtraction problems with small and large numbers. The number of digits in the numbers can be set.

The equal addition subtraction method is also called the ‘borrow and repay’ method or equal additions method for subtraction. Today the method is used in Australia and Latin America. The equal addition used to be a very popular method for subtraction in US until the middle of 20th century.

The equal addition subtraction method

The method is based upon the idea that adding the same amount to two numbers will not affect the difference between the two numbers. The process can be thought as:
- Work column by column from right to left
- When the digit of the first number is smaller than the corresponding digit of the second number, add ten to the digit of the first number and one to the digit of the second number in the next column to the left.

Final app for today is Left-to-Right Subtraction
This app is designed for both iPhone and iPad
  • $3.99
  • Category: Education
  • Updated: Mar 05, 2012
  • Version: 2.0
  • Size: 0.6 MB
  • Language: English
  • Seller: Esa Helttula
Requirements: Compatible with iPhone, iPod touch, and iPad. Requires iOS 5.0 or later.
To purchase the app now please use the following link iTunes

Description

This math app can be used to teach and study the left-to-right subtraction method. The app is easy to use and it has an intuitive interactive interface with customizable colors and other settings. The user can solve random subtraction problems and each step is made clearer with an animation.

The Left-to-right Subtraction Method

The left-to-right subtraction method is a two-step process. In the example 936 - 581, the number to be subtracted is first written in an expanded form: 500+80+1. Each of the parts is then subtracted from the starting number. In our example 936-500=436, 436-80=356 and finally 356-1=355.

In the Everyday Mathematics curriculum the left-to-right subtraction method is one of the algorithms for subtraction.
To find out more about iDevBooks and their apps please visit the following links 












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