To the city

A bus departs for a city 54 km away at an average speed of 15 m/s. A motorcycle departs from the same place 12 minutes after the bus to follow it. Calculate the average speed of the motorcycle if it arrives at the destination at the same time as the bus.

Final Answer:

v₂ =  18.75 m/s

Step-by-step explanation:

$$\begin{gathered} s=54\text{km}\to \text{m}=54\cdot 1000\text{m}=54000\text{m} \\ {v}_1=15\text{m/s} \\ {t}_1=12\text{min}\to \text{s}=12\cdot 60\text{s}=720\text{s} \\ t=s/v_1=54000/15=3600\text{s} \\ {v}_2=\frac{s}{t-t_1}=\frac{54000}{3600-720}=18.75\text{m/s} \end{gathered}$$

Try another example