## Question

A train covers half of its journey with a speed of 20 ms^{–1} and the other half with a speed of 30 ms^{–1}. The average speed of the train during the whole journey is

### Solution

24 ms^{–1}

Let the total journey be 2*x* metres. A distance *x* is covered with a speed of 20ms^{–1} and remaining distance *x* with a speed of 30ms^{–1}. Therefore, total time taken is

#### SIMILAR QUESTIONS

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