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, what is the average of x, y, and z in terms of m? a) m+6 b) m+7 c) 2m+14 d) 3m+21

C

Step-by-step explanation:

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

step-by-step explanation:

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