Correct Answer - Option 3 : 270

**Given:**

Speed of man = 15 m/s

Time taken by good train to cross the man = 30 seconds

Speed of the train = 108 km/h

Length of each compartment = 5 m

**Formula:**

Relative speed while in opposite direction = sum of the speeds

Distance = Speed × Time

Speed in km/h to m/s = multiply by 5/18

**Calculation:**

Speed of good train in m/s = 108 × 5/18 = 30 m/s

Relative speed = (15 + 30) m/s = 45 m/s

Distance covered is length of the train

Distance = 45 × 30 = 1350 m

Length of train = 1350 m

Number of compartments = 1350/5

**∴** **N****umber of compartments is 270**