Answer:
4x
Step-by-step explanation:
Mean of a set of dats is the ratio of the sum of the data to its sample size;
Given the data x, y and z
Mean of the data = 3x
Sample size = 3
Mean = x+y+z/3
3x = x+y+z/3
Cross multiply
3(3x) = x+y+z
9x = x+y+z
y+z = 9x - x
y+z = 8x
Divide both sides by 2
y+z/2 = 8x/2
y+z/2 = 4x
Hence the mean of y and z in terms of x is 4x
