a milk man has 40 liters of milk . if he mixes 5 liters of water , which is freely available , in 20 liters of pure milk . if the cost of pure milk is rs . 18 per liter , then the profit of the milkman , when he sells all the mixture at cost price is :
"explanation : when the water is freely available and all the water is sold at the price of the milk , then the water gives the profit on the cost of 40 liters of milk . therefore , profit percentage = 45 % . answer : c"
multiply(divide(subtract(multiply(add(add(add(20, 5), const_10), add(divide(5, const_2), const_3)), 18), multiply(40, 18)), multiply(40, 18)), const_100)