If x + y = 9, y + z=7 and z + x = What is the average of x, y and z?

A 11/3

B 37/2

C 22/3

D 11

Correct Answer: Option E

x + y + y + z + z + x = 9 + 7 + 9

or, 2x + 2y + 2z = 25

or, (x + y + z) = 25/2

or, average of x, y, z is:

(x + y + z)/3 = 25/6