You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Q: Question: Car ‘X’ covers a distance of 385 kms in 7 hours and car ‘Y’ covers a distance of 715 kms in 13 hrs. What is the difference in the speed of the two cars?

 Option A: 2kms/hr

 Option B: 1km/hr

 Option C: 3kms/hr

 Option D: 5kms/hr

 Option E: None of these

A: Option E
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Q: Question: A train running at the speed of 60 km/hr crosses a pole in 21 seconds. What is the length of the train?

 Option A: 350 m

 Option B: 278 m

 Option C: 876 m

 Option D: 150 m

 Option E: 267 m

A: Option A
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Q: Question: Walking 6/7th of his usual speed, a man is 12 minutes too late. The usual time taken by him to cover that distance is :

 Option A: 1 hr 20 min

 Option B: 1 hr 10 min

 Option C: 1 hr 11 min

 Option D: 1 hr 12 min

 Option E: None

A:
Option D
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