Cyclist 66904

The athlete ran on a 10 km route at a speed of 5 m/s, 10 minutes after him. A cyclist drove at a speed of 30 km/h. Who will be at the finish first (A or B)?

Correct answer:

x = B

Step-by-step explanation:

$$\begin{gathered} s=10\text{km}\to \text{m}=10\cdot 1000\text{m}=10000\text{m} \\ {v}_1=5\text{m/s} \\ {v}_2=30\text{km/h}\to \text{m/s}=30:3.6\text{m/s}=8.33333\text{m/s} \\ T=10\text{min}\to \text{s}=10\cdot 60\text{s}=600\text{s} \\ {t}_1=s/v_1=10000/5=2000\text{s} \\ {t}_2=T+s/v_2=600+10000/8.3333=1800\text{s} \\ {t}_2<t_1 \\ x=B \end{gathered}$$

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