Determine 21903

A truck left place A at 8:00 a.m. at a speed of 60 km/h. From place B, which is 225 km from A, a car drove towards it at a speed of 90 km. Determine when and how far from place A the vehicles meet.

Result

t = 9:30 hh:mm
s₁ =  90 km

Step-by-step explanation:

$$\begin{gathered} s_1+s_2=s \\ {v}_1=60\text{km/h} \\ {v}_2=90\text{km/h} \\ s=225\text{km} \\ {v}_1\cdot (x-8.00)+v_2\cdot (x-8.00)=s \\ 60\cdot (x-8.00)+90\cdot (x-8.00)=225 \\ 150x=1425 \\ x=\frac{1425}{150}=9.5 \\ x=\frac{19}{2}=9.5 \\ t=x=9.5=9:30\text{hh}:\text{mm} \end{gathered}$$

$s_1=v_1\cdot (x-8.00)=60\cdot (9.5-8.00)=90\text{km}$

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