Write in km/h a speed of 18 km in 10 min
\(1h=60min\to1min=\frac{1}{60}h\\\\\frac{18\ km}{10\ min}=\frac{18}{10}\ km/min=1.8\ km/min=1.8\times\frac{km}{\frac{1}{60}\ h}=(1.8\times60)\ km/h\\\center=\boxed{108\ km/h}\)