SOLUTION: if 5a+5b=45, what is the average(arithmetic mean) of a and b?

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Question 316869: if 5a+5b=45, what is the average(arithmetic mean) of a and b?
Found 2 solutions by Fombitz, checkley77:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
5a%2B5b=45
a%2Bb=9
%28a%2Bb%29%2F2=9%2F2
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The average of a and b is 9%2F2

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
5a+5b=45
5(a+b)=45
a+b=45/5
a+b=9
9/2=4.5 ans. for the average of a & b.
Proof:
5*4.5*4.5=45
22.5+22.5=45
45=45