Question

hello i am currently working on some examples given with the answers in the back, so i was wondering if someone could help me with this problem: bank was paid $19.48 interest at 9.5% for 90 days and now i need to find out the amount borrowed, i set up the formula 19.48 .095*90/360, * the denominator, divided the numerator by .02375 according to the book the answer is $820.21, i cannot get to that number what am i missing? help this very new student to algebra thanks in advance