HELP SOMEONE PLZ HELPP RIGHT NOW!!

Ricky takes out a $31,800 student loan to pay his expenses while he is in college. after graduation, he will begin making payments of $190.66 per month for the next 30 years to pay off the loan. how much more will ricky end up paying for the loan than the original value of $31,800? ricky will end up paying $ more than he borrowed to pay off the loan.

I’m really confused and need to learn this

Xy x xy if a and b are positive integers such that a*b=9 and b*a=72 what is the value of a/b