Please explain in writting how you find the formula. Please write down explanation, not just the final answer.
Assume that you have a balance of $8000 on your MasterCard and that you make no more charges. Assume that MasterCard charges 12% APR and that each month you make only the minimum payment of 5% of the balance.
Find a formula for the balance B after t monthly payments. (Enter numerical values to four decimal places.)