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If the average of 12, 7, 9, a, and b is 12, thenwhat is the average of a + b?

User Eydelber
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1 Answer

6 votes
6 votes

If the average of 12, 7, 9, a, and b is 12, then

what is the average of a + b?

we know that

the average is equal to

(12+7+9+a+b)/5=12

simplify

(28+a+b)/5=12

Multiply both sides by 5

28+a+b=60

isolate (a+b)

a+b=60-28

a+b=32

average a+b

a+b/2=32/2=16

answer is 16

User Burcak
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