Question

A train 108 m long moving at a speed of 50 kmph crosses a train 112 m long coming from opposite direction in 6 seconds. The speed of the second train is

• A. 48 kmph
• B. 54 kmph
• C. 66 kmph
• D. 82 kmph

Answer 1

The correct option is D 82 kmph

$\text{Let the speed of the second train be}x\text{kmph}\text{Relative speed}=(x+50)kmph=\left[\right(x+50)\times \frac{5}{18}]m/sec.=\left(\frac{250+5x}{18}\right)m/sec.\text{Distance covered}=(108+112)=220m.\therefore \frac{220}{\left(\frac{250+5x}{18}\right)}=6or250+5x=660$