Two express trails of length 320 m and 380 m started moving from Ahmedabad to Delhi at the same time. Their speeds are 84 km/h and 41 km/h respectively. In how many seconds will the faster train cross the slower train? 

Correct option is C

Given:

Length of the faster train (Train 1) = 320 m

Length of the slower train (Train 2) = 380 m

Speed of the faster train = 84 km/h

Speed of the slower train = 41 km/h

Time = ?

Formula Used:

​$$time= \frac{Distance}{Relative\ speed}$$

Solution:

Faster train: 84 km/h = $$\frac{84\times1000}{3600}$$ = 23.33 m/s

​Slower train: 41km/h = $$\frac{41\times1000}{3600}$$ = 11.39 m/s

​Relative Speed = 23.33m/s - 11.39 m/s = 11.94m/s

total distance covered ,

320 m + 380m = 700m 

Time = $$\frac{700m}{11.94m/s}$$

Time = 58.64 seconds

Rounding to the nearest second, the time is approximately 60 seconds.

thus, correct option is (c)