Let the C.P of 10 apples = S.P of 8 apples = x
Then C.P of each apple = x/ 10
And S.P of each apple = x/ 8
Now x / 8 > x / 10
It means S.P > C.P , therefore it is Profit = S.P- C.P ( formula of profit )
So x / 8 - x / 1 0
= (10x - 8x ) / 80
= 2x / 80
= x/ 40
So we will get profit = x / 40
Now , we will find Profit %
Formula of Profit % = Profit / C.P * 100
So x / 40 / x / 10 * 100
= x / 40 * 10/ x * 100
= 100/ 4 , so we will get 25 % .
( B ) option , 25 % , that would be the final answer