Question

A train crosses two bridges 370 m and 480 m long in 51 and 62 seconds respectively. Find the speed of the train. 
a)24 kmph b)36 kmph c)45 kmph d)64 kmph 

Answer 1

the answer is in the picture below

Answer 2

Answer:

(B)

Step-by-step explanation:

Let x be the length of the train, then according to the question,

$\frac{x+370}{51}=\frac{x+480}{62}$

$62(x+370)=51(x+480)$

$62x+22940=51x+24480$

$11x=1540$

$x=140 m$

Taking the length of the 2nd bridge into consideration,

Speed of the train=$\frac{x+480}{62}=\frac{140+480}{62}=\frac{620}{62}=10{\times}\frac{18}{5}=36kmhr^{-1}$