Practice Test Discussion

Q)

A train travles from A to B at the rate of 20 km per hour and from B to A at the rate of 30 km/hr. What is the average rate for the whole journey?


  • Explanation

    According to the question,

    A=20, B=30

    we know the formula,

    Average speed= 2ABA+B

    The average rate for the whole journey=2×20×3020+30= 24 km/hr

    Hence, Option D is correct.

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