A 320 metre long train crosses a pole in 16 seconds . It stops five times of duration 18 minutes each . What time will it take in covering a distance of 576 km ?

Options

A. 9 hours
B. `9(1)/(4)` hours
C. `9(1)/(2)` hours
D. `8(1)/(2)` hours

Answer

C

Explanation

Speed of train = `("Length of train")/("Time taken in crossing ")`
= `(320)/(16) = 20`m/sec
`= 20 xx (18)/(5) = 72` kmph
Total period of stoppage = `5 xx 18`
= 90 minutes = `(3)/(2)` hours
Total time taken in covering a distance of 576 km.
`= ((576)/(72) + (3)/(2)) ` hours = `8 + (3)/(2) = 9(1)/(2)` hours