Cars

Cars started at 7:00 AM.
From point A, the car runs at 40 km per hour, and from B, the car runs at 70 km per hour. Between A and B is a 250 km long road.

When and where will they meet (measured from point A)?

Result

T = 9:16 hh:mm
s₁ =  90.91 km

Step-by-step explanation:

$$\begin{gathered} s_1=v_{1}t \\ {s}_2=v_{2}t \\ s=s_1+s_2=v_{1}t+v_{2}t=t(v_1+v_2) \\ t=\frac{s}{v_1+v_2}=\frac{250}{40+70}=2.27h \\ T=7+t=9:16\text{hh}:\text{mm} \end{gathered}$$

$s_1=v_{1}t=40\cdot 2.27=90.91\text{km}$

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