For a 30-year, $300,000 mortgage, use a spreadsheet to determine the annual rate you will have to lock in to have payments of $1800 per month. How large a loan can you take out at an annual rate of...

For a 30-year, $300,000 mortgage, use a spreadsheet to determine the annual rate you will have to lock in to have payments of $1800 per month.

How large a loan can you take out at an annual rate of 15% if you can afford to pay back $1000 at the end of each month and you want to retire the loan in 5 years?