Mark owes $$875$ in $4$ years and $$1050$ in $9$ years. However, Mark is unable to meet his $$875$ obligation at the end of $4$ years. By mutual agreement with the lender, Mark is allowed to pay off both obligations at the end of $7$ years based on a simple interest rate of $6\mathrm{.}25\%.$ Determine the amount required to settle the debts at the end of $7$ years.