robert ' s salary was decreased by 50 % and subsequently increased by 50 % . how much percentage does he lose ?
"let original salary be $ 100 new final salary = 150 % of ( 50 % of $ 100 ) = ( 150 / 100 ) * ( 50 / 100 ) * 100 = $ 75 decrease = 25 % correct option is c"
multiply(divide(subtract(multiply(const_100, const_100), multiply(subtract(const_100, 50), add(const_100, 50))), multiply(const_100, const_100)), const_100)