Question

if the mean of x, x+2,x+4,x-6 and x+8 is 11, what is average of the last three numbers ?? A)11 B)13 C)14 4)15

Answer 1

Mean = x+x+2+x+4+x-6+x+8÷5
11=5x+2+4-6+8÷5
11*5=8+5x
55-8÷5=x
X= 53.4