On December 31, 2017, Roper Company had current assets (cash) of $15,000 and current liabilities (accounts payable) of $8,000, resulting in a current ratio of 1.88. The company needs to increase its current ratio to 2.75 by December 31, 2018. Calculate the amount of accounts payable that needs to be paid in order to boost the current ratio to 2.75.