Calculate total length of the train

The train has 24 carriages and 1 engine, totaling 25 units. Each is 60m long.

$Length_{train} = 25 \times 60 = 1500 m = 1.5 km$

Determine total distance to cross

To fully cross the bridge, the train must cover the bridge length plus its own length.

$\text{Distance} = 1.5 km (bridge) + 1.5 km (train) = 3.0 km$

Calculate time taken

Using time = distance/speed with the given speed of 50 km/h.

$\text{Time} = \frac{3 km}{50 km/h} = 0.06 hours$

Convert hours to minutes

Multiply the time in hours by 60 to get minutes.

$0.06 \times 60 = 3.6 min$