After you submit your loan application, the lender does an extensive check on your finances and credit record. If everything checks out, the lender will state the exact amount they're willing to loan you. The preapproval is good for a set amount of time, usually 60–90 days.
3% is the interest so you would do 3% of the investment plus the original investment so 3%×I=z and then z+I=the answer. sorry if this didnt help I'm new and I tried my best sorry!