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A credit card charges 18 percent annual interest and Frank has S750 due on the statement date. He is only able to make the minimum payment of $22.50. If the billing cycle is 30 days and the grace period is 20 days, and he pays the full balance at the next due date, how much interest would he owe? A: S28.70 Fred has a credit card which uses the average daily balance method, has a 30-day billing period, a 21-day grace period and charges 21 percent annual interest calculated (but not compounded) daily. His average daily balance for the billing period was $7900, and he could not pay it off until received his pay cheque eight days after the statement due date. How much interest does he owe? A: $268.17 If a credit card company has a 30-day billing period, 20-day grace period and an interest rate of 20 percent, how much interest will be charged on a $5000 average monthly balance which gets paid 40 days after the due date using the average daily balance method? A: $258.90