Question

Arithmetic mean of a-b and a+b is ______

Answer 1

Answer:

Let the a,b & c be a-d,a & a+d

now mean of a&b =x

(a-d+a)/2 =x

(2a-d)/2=×

mean of b&c=y

(a+a+d)/2=y

(2a+d)/2=y

now mean of ×&y=(x+y)/2

={(2a-d)/2+(2a+d)/2}/2

={(4a)/2}/2

=a