finance
posted by lindaemory .
shawn bought a home for $100000.he put 20% down and obtained a mortgage for 30 years at 51/2%.what is the total interest cost of the loan? i need the steps worked.

% Loan = 100%  20% = 80%.
Amt of Loan = 0.8 * $100,000 = $80,000.
Pt = Po*r*t / (1(1+r)^t),
r = (5.5% / 12) / 100$ = 0.00458 = monthly % rate expressed as a decimal.
t = 30yrs * 12mo/yr = 360mo.
Pt=80000*0.004583333*360/(1(1.004583333)^360 = $163,523.23. 
Int. = 163,523.23  80,000 = $83,523.23

well, the answer came out in ics as $104,480.00 but as i figured it 100,000/1000=100x5.68 so 5.68x360=204,480.00100000.00=$104,480.00 that was i got but see is the 20% figured in that figure?

$63,584.00is the correct answer.
$80 x 5.68 = 454.40
454.40 x 360 = 163,584.00
163,584.00  100,000 = $63,584.00
D.) $63,584.00