if difference between compound interest and simple interest on a sum at 10 % p . a . for 2 years is rs . 41 then sum is
"p ( r / 100 ) ^ 2 = c . i - s . i p ( 10 / 100 ) ^ 2 = 41 4100 answer : e"
divide(41, multiply(divide(10, const_100), divide(10, const_100)))