Answer:
x - 17
Step-by-step explanation:
hope that helps
C
If x is the average (arithmetic mean) of m and 9, y is the average of 2m and 15, and z is the average of 3m and 18,
x=(m+9)/2
y=(2m+15)/2
z=(3m+18)/2
the average of x, y, and z
=(x+y+z)/3
=(m+9+2m+15+3m+18)/3
=(6m+42)/3
=2m+14
ans is C
11th number is 6
the second one
-1 -2
3 0
5 1
7 2