if a lends rs . 3150 to b at 8 % per annum and b lends the same sum to c at 12.5 % per annum then the gain of b in a period of 2 years is ?
"( 3150 * 4.5 * 2 ) / 100 = > 283.5 answer : c"
subtract(divide(multiply(multiply(3150, 12.5), 2), const_100), divide(multiply(multiply(3150, 8), 2), const_100))