SOLUTION: Multiple Choice: if one half the average of 3 numbers a, b and c is equal to twice the average of a and b, then c=____. a) 2(a+b) b) 3(a+b) c) 4(a+b) d) 5(a+b)

Question 1059597: Multiple Choice: if one half the average of 3 numbers a, b and c is equal to twice the average of a and b, then c=____.
a) 2(a+b) b) 3(a+b) c) 4(a+b) d) 5(a+b)
Answer by KMST(5328) (Show Source): You can put this solution on YOUR website!
The average of all 3 numbers is .
The average of and is .
The problem says that

which simplifies to
.
Multiplying both sides of the equal sign times . we get the equivalent equation

Subtracting from both sides of the equal sign we get
, which simplifies to
.
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