Math
posted by Liz .
Can you please explain this to me.
The problem is 7/16  3/20
First I have to find the common denominator which would be 80
How does the 7/16 become 35/80 (where does the 35 come from)
How does the 3/20 become a 12/80 (Where does the 12 come from)
35/80 minus 12/80
answer 23/80

Math 
bobpursley
7/16*5/5= 35/80
3/20 * 4/4= 12/80 
Math 
Liz
I still don't get it???

Math 
bobpursley
What you don't understand it how to get a common denominator...
http://www.mathsisfun.com/numbers/commondenominator.html
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