Drexel dragonThe Math ForumDonate to the Math Forum

Ask Dr. Math - Questions and Answers from our Archives
_____________________________________________
Associated Topics || Dr. Math Home || Search Dr. Math
_____________________________________________

Multiplying Unlike Fractions


Date: 4/1/96 at 7:14:46
From: Leigh Ausband
Subject: Multiplying unlike fractions

From Mrs. Fields' seventh grade math classes at 
Robert Smalls Middle School, Beaufort, SC.

Dear Dr. Math,

What is the fastest way to multiply unlike fractions? For
example 5/9 * 2/12.

Kevin O'Brien


Date: 4/2/96 at 4:2:32
From: Doctor Jodi
Subject: Re: questions for Dr. Math: Kevin O;Brien

Hi Kevin!

Multiplying unlike fractions isn't any different from multiplying 
fractions with the same denominator, surprisingly enough!

We just multiply the numerators and multiply the denominators.

So

  5     2      10
  -  * --  =  ---
  9    12     108
 
We can then put 10/108 into lowest terms:


 10      5    2      5
 --  =  --  * -  =  --  * 1
108     54    2     54


So 5/9 * 2/12 = 5/54

Ok, so here's a question for you Kevin:

what's 3/8 * 5/6?

-Dr. Jodi
  http://mathforum.org/dr.math/   
    
Associated Topics:
Elementary Fractions

Search the Dr. Math Library:


Find items containing (put spaces between keywords):
 
Click only once for faster results:

[ Choose "whole words" when searching for a word like age.]

all keywords, in any order at least one, that exact phrase
parts of words whole words

Submit your own question to Dr. Math

[Privacy Policy] [Terms of Use]

_____________________________________
Math Forum Home || Math Library || Quick Reference || Math Forum Search
_____________________________________

Ask Dr. MathTM
© 1994-2013 The Math Forum
http://mathforum.org/dr.math/