Question

the train in km/hr.
A train 150 m long is running at 72 km/hr. It crosses a bridge in 13 seconds. Find
the length of the bridge. Answer in direct and inverse variation​

Answer 1

(length of bridge + length of train) = speed of train * time to cross bridge

So:

x + 150 = 72km/h * 13s

Convert 72km/h to m/s => 72000m/3600s => 20m/s (speed of train)

Now, solve:

x + 150m = 20m/s *13s => x + 150m = 260m => x = 260m - 150m => x = 110m (length of bridge)