The arithmetic mean of x,y andz is 6 while that of x,y,z,t,u,v and w is 9. Calculate the arithmetic mean of t,u,v and w

1 answer

Ok. I'll show some maybe-not-so-divine mercy and help you out.

(x+y+z)/3 = 6
(x+y+z+t+u+v+w)/7 = 9

x+y+z = 18
x+y+z+t+u+v+w = 63

18+t+u+v+w = 63
t+u+v+w = 45

(t+u+v+w)/4 = 45/4