If x+y=6, y+z=7 and z+x=9, what is the average(arithmetic mean) of x, y and z?
A)11/3
B)22/3
C)11
D)22

Question

Quizplus · Accepted Answer

Add the three equations
x+y=6
y+z=7
z+x=9
__________
2x +2y +2z =22
x+y+z = 11
or (x=y+z)/3 = 11/3
Key takeaway: First have a close look at the pattern of the give equations for any simpleway to attack such problems. Sometimes simply adding or subtracting the equations may yield the desired result.

If X+y=6, Y+z=7 and Z+x=9, What Is the Average(arithmetic Mean)