by selling 8 pencils for a rupee a man loses 60 % . how many for a rupee should he sell in order to gain 60 % ?
"40 % - - - 8 160 % - - - ? 40 / 160 * 12 = 2 answer : c"
multiply(divide(const_1, multiply(add(const_100, 60), divide(const_1, subtract(const_100, 60)))), 8)