Assigning Value to Assets in Nonmonetary Exchange Lacking Commercial Substance

Mariot trades in its old equipment $($with the following carrying values$)$ for new equipment. Mariot received $$6,000$ cash on the exchange. The fair value of the new

equipment is $$21,000.$

If the transaction lacks commercial substance, what amount does Mariot assign to the new equipment?

Note: Carry all decimals in calculations; round the final answer to the nearest dollar.