Question

if the arithmetic mean between x and 7 is 9 than what is x ?

Answer 1

Arithmetic mean = (a+b)/2
9 = (x+7)/2
18 = x+7
x=18-7 = 11

So the value of x is 11

Answer 2

Arithmetic mean =a+b/2 9=x+7/2 18-7=x=11