if a man lost 10 % by selling oranges at the rate of 18 a rupee at how many a rupee must he sell them to gain 32 % ?
"90 % - - - - 18 132 % - - - - ? 90 / 132 * 18 = 12.27 answer : d"
divide(multiply(subtract(const_100, 10), 18), add(const_100, 32))