D'anthony borrowed $50,000 today that he must repay in 15 annual end-of-year installments of $5,000. what annual interest rate is d'anthony paying on his loan?

D'anthony borrowed $ 50,000, which is the principal amount.

The repayment was $5,000 per year therefore after 15 years he will have paid a total of 15 * $ 5000 = $75,000.

Therefore, the interest accrued will be $75,000 - $ 50,000 = $ 25,000

By calculation interest is given by principal * rate*time

hence, rate = interest * 100 / principal * time

= 25,000 * 100 / 50,000 * 15

= 3.333%

Therefore, the rate of interest was 3.33% per annum