Car overtaking

The car moved out of place at a speed of 60 km/h in 1.5 hours. The second car moved at a speed of 80 km/h. How long will it take to catch the first car, and how many kilometers will it drive?

Final Answer:

t =  4.5 h
s =  360 km

Step-by-step explanation:

$$\begin{gathered} v_1=60\text{km/h} \\ {v}_2=80\text{km/h} \\ \Delta t=1.5\text{h} \\ s=v_1\cdot (t+\Delta t) \\ s=v_2\cdot t \\ {v}_1\cdot (t+\Delta t)=v_2\cdot t \\ 60\cdot (t+1.5)=80\cdot t \\ 20t=90 \\ t=\frac{90}{20}=4.5 \\ t=\frac{9}{2}=4.5=4.5\text{h} \end{gathered}$$

$s=v_2\cdot t=80\cdot 4.5=360\text{km}$

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