My brothers stuck on these 2 problems and won’t stop bothering me so can someone help him

What number produces an irrational number when multiplied by -1.25

Anyone know? will mark brainliest if you're correct!

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.