robert ' s salary was decreased by 60 % and subsequently increased by 60 % . how much percentage does he lose ?
let original salary be $ 100 salary after decreasing 60 % = 100 - 100 x 60 / 100 = $ 40 salary after increasing 60 % on $ 40 = 40 + 40 x 60 / 100 = $ 64 percentage of loss = 100 - 64 = 36 % answer : d
multiply(divide(subtract(multiply(const_100, const_100), multiply(subtract(const_100, 60), add(const_100, 60))), multiply(const_100, const_100)), const_100)