a person buys an article at rs . 500 . at what price should he sell the article so as to make a profit of 20 % ?
explanation : cost price = rs . 500 profit = 20 % of 500 = rs . 100 selling price = cost price + profit = 500 + 100 = 600 answer : a
add(500, multiply(500, divide(20, const_100)))