profit and loss definition - Interview Questions

profit and loss definition

A storekeeper sold a wrist watch for $660, including a sales tax of 10%. If the cost price of the watch is $500, what is the percentage profit for shopkeeper ?

Answer : D. 20%

A trader bought a car at 20% discount on its original price. He sold it at a 40% increase on the price he bought it. What percent of profit did he make on the original price ?

Answer : C . 12 %