Sophia exchanged 1,000 u. s. dollars for the south african currency, which is called the rand. the exchange rate was 8.55 rand to $1.how do you do this question

Dakota earned $7.50 in interest in account a and $18.75 in interest in account b after 15 months. if the simple interest rate is 4% for account a and 5% for account b, which account has the greater principal? explain. to make it a little easier, there is an image. good luck!