What's New

Minor bug fixes and enhancements.

App Description

A power learning aid combining Coaching Calculators and Guides to help students master prime factorization, LCM and GCD.

Prime factorization :

- Prime factorization by factor trees

LCM or Least Common Multiple :

- LCM by prime factorization

- LCM by listing multiples

GCD or Greatest Common Divisor :

- GCD by prime factorization

- GCD by listing divisors

You develop understanding quickly as you work with the calculator and see each step of the process in detail.

iPhone Screenshots

(click to enlarge)

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iPad Screenshots

(click to enlarge)

20/20 Primes and Factor Trees screenshot 11 20/20 Primes and Factor Trees screenshot 12 20/20 Primes and Factor Trees screenshot 13 20/20 Primes and Factor Trees screenshot 14 20/20 Primes and Factor Trees screenshot 15 20/20 Primes and Factor Trees screenshot 16 20/20 Primes and Factor Trees screenshot 17 20/20 Primes and Factor Trees screenshot 18 20/20 Primes and Factor Trees screenshot 19 20/20 Primes and Factor Trees screenshot 20

App Changes

  • June 24, 2011 New version 2.2
  • July 04, 2012 New version 3.0
  • September 29, 2012 New version 3.1
  • February 21, 2013 New version 3.2
  • September 29, 2013 New version 4.0
  • November 26, 2013 New version 4.1
  • February 21, 2015 New version 5.0
  • September 17, 2015 New version 5.1
  • November 09, 2016 New version 6.0
  • June 14, 2019 New version 7.2
  • June 14, 2019 Price increase: FREE! -> $0.99
  • June 14, 2019 Price increase: FREE! -> $0.99
  • June 15, 2019 Price increase: FREE! -> $0.99
  • June 15, 2019 Price increase: FREE! -> $0.99
  • June 15, 2019 Price increase: FREE! -> $0.99
  • June 17, 2019 Price increase: FREE! -> $0.99
  • September 24, 2019 New version 7.3
  • September 27, 2019 New version 7.4
  • October 29, 2019 New version 7.6
  • January 14, 2020 New version 7.7
  • January 14, 2020 Price decrease: $0.99 -> FREE!
  • January 28, 2020 New version 7.8
  • January 28, 2020 Price increase: FREE! -> $0.99