Cost of house: $127,000
Down payment: 25% of $127,000 = $31,750
Principal financed: $127,000 - $31,750 = $95,250

where A = monthly payment,
P = principal borrowed
r = interest rate per period
n = number of periods
8% loan:
n = 30 * 12 = 360
r = 8/100/12 = 0.08/12
P = $95,250


A = $698.9107566 per month
In 360 months, you pay 360 of those payments, for a total of
$251,607.87238
6% loan:
n = 30 * 12 = 360
r = 6/100/12 = 0.06/12 = 0.005
P = $95,250


A = $571.07187 per month
In 360 months, you pay 360 of those payments, for a total of
$205,585.87507
Now subtract the amounts of total payments to find the difference in interest: $251,607.87238 - $205,585.87507 = $46,021.9973
Answer: $46,022.00