A 50 meter long train passes over a bridge at the speed of 30 km per hour. If it takes 36 seconds to cross the bridge, what is the length of the bridge?

A. 200 meters

B. 250 meters

C. 300 meters

D. 350 meters

Answer: Option B

Solution(By Examveda Team)

Speed = $$\left( {30 \times \frac{5}{{18}}} \right)$$  m/sec = $$\frac{{25}}{3}$$ m/sec
Time = 36 second
Let the length of the bridge be x meters.
Then, $$\frac{{50 + {\text{x}}}}{{36}}$$   = $$\frac{{25}}{3}$$
⇒ 3(50 + x) = 900
⇒ 50 + x = 300
⇒ x = 250 meters