4. Vanna has just financed the purchase of a home for $200 000. She agreed to repay the loan by making equal monthly blended payments of $3000 each at 9%/a, compounded monthly.

Determine how much interest she will pay for her loan.

h. How much would Vanna have saved if she had obtained a loan at 7%/a, compounded monthly?

Can anyone give me the formulas please ? I can do the rest myself...