Question

lowell has a credit card that uses the adjusted balance method. for the first 10 days of one of his 30-day billing cycles, his balance was $1360. he then made a purchase for $470, so his balance jumped to $1830, and it remained that amount for the next 10 days. lowell then made a payment of $470, so his balance for the last 10 days of the billing cycle was $1090. if his credit card's APR is 28%, which of these expressions could be used to calculate the amount lowell was changed in interest for the billing cycle?

Answer 1

any idea ?