# The length of the bridge, which a train 130 metres long and travelling at 45 km/hr can cross in 30 seconds, is:

A. 200 m

B. 225 m

C. 245 m

D. 250 m

**Answer: Option C **

__Solution(By Examveda Team)__

$$\eqalign{
& {\text{Speed}} = {45 \times \frac{5}{{18}}} \,{\text{m/sec}} \cr
& \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = {\frac{{25}}{2}} \,{\text{m/sec}} \cr
& {\text{Time}} = 30\,{\text{sec}} \cr
& {\text{Let}}\,{\text{the}}\,{\text{length}}\,{\text{of}}\,{\text{bridge}}\,{\text{be}}\,x\,{\text{metres}} \cr
& {\text{Then}},\,\frac{{130 + x}}{{30}} = \frac{{25}}{2} \cr
& \Rightarrow 2\left( {130 + x} \right) = 750 \cr
& \Rightarrow x = 245\,m \cr} $$ ## Join The Discussion

## Comments ( 2 )

Related Questions on Problems on Trains

A. 120 metres

B. 180 metres

C. 324 metres

D. 150 metres

A. 45 km/hr

B. 50 km/hr

C. 54 km/hr

D. 55 km/hr

A. 200 m

B. 225 m

C. 245 m

D. 250 m

5/18 is used for converting km/hr to m/s

How did u get 5 / 18 in this sum please revert