Answer:
Use his savings to buy the shoes now and put the amount he is short on a credit card.
Explanation:
Due to the discount on sale, then it is advisable James buys with his savings and put the balance amount on his credit card. By virtue if the discount, James will be able to save ;
(0.2* $240) = $48. This discount will be a good bargain and will be unavailable by the time his savings can buy in full. However, since James has a repayment channel (his $20/week) saving, then he can put the amount left to balance in his credit card and sort his credit balance later.