[tex]speed = \frac{distance}{time} \\ = > \frac{200m}{min} = \frac{1500m}{t} \\ = > \frac{200m}{60s} = \frac{1500m}{t} \\ = > \frac{10m}{3s} = \frac{1500m}{t} \\ = > t = 1500m \times \frac{3s}{10m} \\ = > t = 150 \times 3s \\ = > t = 450s \: [/tex]
This is the answer.
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