a number exceeds 20 % of itself by 40 . the number is ?
answer ∵ a - 20 % of a = 40 ⇒ a - a / 5 = 40 ⇒ 4 a / 5 = 40 ∴ a = ( 5 x 40 ) / 4 = 50 . correct option : a
divide(40, subtract(const_1, divide(20, const_100)))