Answer:
$960
Explanation:
After paying 20% down, Chuck's loan amount is for ...
... $240,000 × (100% -20%) = $240,000 × 0.80 = $192,000
The interest amount in the first payment is one month's interest on this amount. The monthly interest rate is 1/12 of the annual rate.
... 6%/12 × $192,000 = 0.005 × $192,000 = $960
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Comment on the problem statement
My mortgage calculator computes the monthly payment as $1237.06.