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Multiplying Fractions and a Whole Number

Date: 16 May 1995 18:13:46 -0400
From: earl perkins
Subject: request for help

Right now I'm multiplying fractions and whole numbers.
It's kind of hard to give an example. I'll try to give you some.


Date: 16 May 1995 23:37:23 -0400
From: Dr. Sydney
Subject: Re: request for help

Dear Ethan,

What kinds of problems do you mean?  For instance, would you be able to 
do these problems?

1)       1
   3 x  ---  = ?

2)  2
   ---  x 2 = ?

Tell me if these are the kind of problems you are working with, and I'll 
try to help you out, okay?  I look forward to hearing from you!

--Sydney, "dr.math"

Date: 16 May 1995 23:37:23 -0400
From: earl perkins
Subject: Re: request for help

Hold on, you are right, those are the problems I'm doing!
Yep, those are the problems I'm working on!


Date: 21 May 1995 18:33:26 -0400
From: Dr. Sydney
Subject: Re: request for help

Hello, Ethan!  

Sorry it took a while for me to get back to you--I've not been at the
computer for a few days!

Okay, well I'm glad we've found examples of the kinds of problems you are
working on, but I'm not sure exactly where you are having problems.  So, 
why don't we do an example problem, okay?

How about the problem:

--- x 4 = ?

When you are multiplying a fraction and a whole number, all you do, is
multiply the numerator of the fraction (the number on top) by the whole
number, and put that number over the denominator (the number on bottom).
So, for this problem, we would simply multiply 3 by 4 and put it over 5.
Since 3 times 4 is 12, our answer would be 12/5  (You may want to simplify
this into a compound fraction; write back if you aren't sure how!).  Does
that make sense?  

Why don't you try a few problems!  If you would like to try the two at the
bottom of this message and check you answer with us, that would be fine.
Or, if you would like to do even more practice problems, feel free to write
back, and we can give you more. 

Here is another thing to think about when you are doing these problems --
when would you multiply a fraction by a whole number in real life?  Can you
think of examples where this would be useful?  What if you and 4 other
friends got a pizza so that each of you wanted 1/5 of the pizza.  If the
pizza has 8 slices, how can you figure out how many slices of pizza each
of you should get?

Write back if you have any more questions!

--Sydney, "dr. math"
Associated Topics:
Elementary Fractions

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