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# A train takes 10 seconds to cross a pole and 20 seconds to cross a platform of length 200 m. What is the length of the train?

 A) 50 m B) 100 m C) 150 m D) 200 m

 D) 200 m

Let 'L' be the length of train

A train takes 10 sec to cross a pole $$\Large S_{T} = \frac{L}{10}$$... (i)

and same train takes 20 sec to cross a platform of length 200 m

$$\Large S_{T} = \frac{L+200}{20}$$...(ii)

Solving equation (i) and (ii) we get

$$\Large \frac{L}{10} = \frac{L + 200}{20}$$

2L = L + 200

L = 200m

Hence length of train is 200 m

Option (D)is correct

Part of solved CDS Maths(1) questions and answers : Exams >> CDSE >> CDS Maths(1)

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