Q. A train of length 500 feet crosses a platform of length 700 feet in 10 seconds. The speed of the train is :
Answer: 120 ft/sec
Notes: $latex Speed\ of\ train\ = \frac{Length\ of\ (train+platform)}{Time\ taken\ to\ cross}&s=1$ $latex = \left ( \frac{500+700}{10} \right ) = 120\ feet/ sec.&s=1$ Hence option [D] is correct answer.

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