Question

If the average(arithmetic mean) of 5 and r is 7 and the average of 3 and s is 3 , what is the average of r and s?

A) 3
B) 5
C) 6
D) 9

Answer 1

C

Explanation:

Calculate the values of both r and s, that is

`(5+r)/(2)` = 7 ( multiply both sides by 2 )

5 + r = 14 ( subtract 5 from both sides )

r = 9

and

`(3+s)/(2)` = 3 ( multiply both sides by 2 )

3 + s = 6 ( subtract 3 from both sides )

s = 3

Hence

`(9+3)/(2)` =
`(12)/(2)` = 6 → C