Daphne bought a house for 335,000. she financed 276,475 of the purchase price with a 30 year, fixed rate mortgage with 5.65% interest rate. what is the total cost of the principal and interest after 30 years

First find the yearly payment using the formula of the present value of annuity ordinary
The formula is
Pv=pmt [(1-(1+r)^(-n))÷r]
Pv present value 276475
Pmt yearly payment ?
R interest rate 0.0565
N time 30 years

Now solve for pmt
The formula change to be
Pmt=pv÷ [(1-(1+r)^(-n))÷r]
Plug in the equation above
Pmt=276,475÷((1−(1+0.0565)^(−30))÷(0.0565))=19,339.22

Now find the cost of the principle and interest after 30 years by multiplying the yearly payment by the time

19,339.22×30=580,176.60...answer

Hope it helps:-)