37. In the parking lot, only two-wheeled motorcycles and four-wheeled cars are parked, and the number of motorcycles is more than the number of cars. The two types of vehicles have a total of 84 wheels. After 3 vehicles are driven away, the number of wheels in the parking lot is 3 times the number of vehicles. Originally, there were $\qquad$ motorcycles parked in the parking lot.
\begin{tabular}{l}
$\mathbf{3 7}$ \\
\hline 16
\end{tabular}