A customer bought a product at the shop. However, the shopkeeper increased the price of the product by 20% so that the customer could not buy the required amount of the product. The customer managed to buy only 70% of the required amount. What is the difference in the amount of money that the customer paid for the second purchase compared to the first purchase? Options:
A) 16 %  B) 18 %  C) 20 %  D) 22 %  E) 24 %

Rationale: let x be the amount of money paid for the first purchase . the second time , the customer paid 0.7 ( 1.2 x ) = 0.84 x . the difference is 16 % . the answer is a .
Answer: A