below is an example

Use the average daily balance method to compute the finance charge on the credit card account for the previous month. The starting balance and transactions on the account for the month of April are given to the right. Assume an annual interest rate of 18% Month: April (30 days); previous month's balance: $550 April 14 Charged $43 for a coat April 19 Made payment of $510 April 24 Charged $143 for DVDs April 26 Charged $20 for groceries The finance charge is $ (Round to the nearest cent as needed.) 30 Use the formula for finance charge, I = Prt, with P = $435.10, r=0.18, and t = 365 ,rounding to the nearest cant. 1 = Prt = $435.10(0.18) 30 365 = $6.44