The average of x and y is 5 and the average of x,y, and z is 8. What is the value of z?

a. 19
b. 14
c. 13
D. 11
e. 3
I know that the average of 7 and 3 is 5 (if 7 and 3 are x and y) but I don't know what z is.

2 answers

I would solve it this way:

z+x+y=5+5+z=3*8

z=24-10
answer is b.14 add 7(x) + 3(y) + 14(try each multiple choice;0)gives u 24 divided by 3 tada 8!!!