if a lends rs . 2800 to b at 15 % per annum and b lends the same sum to c at 18.5 % per annum then the gain of b in a period of 3 years is ?
"( 2800 * 3.5 * 3 ) / 100 = > 294 answer : a"
subtract(divide(multiply(multiply(2800, 18.5), 3), const_100), divide(multiply(multiply(2800, 15), 3), const_100))