Suppose you buy a home and finance $255,000 at $2,293.17 per month for 30 years. What is the amount of interest paid? (Round your answer to the nearest cent.)

Answer 1

They probably just want you to do this:
$2293.17(360) - $255,000 = $570,541.20

However that is an invalid operation and invalid question,
since the calculation covers different intervals of time.
e.g. $1000 today is not the same value as $1000 five years from now.

A more interesting question would have been, what was the rate of interest?