Correct Answer - Option 4 : 24

**Given **

Covered by rail = 2/15 of his total journey

Covered by car = 9/20 of his journey

**Formula used **

Distance = speed × Time

**Calculation **

Let the total distance be x

Distance covered by walking = 10 km

⇒ (x - 2x/15 - 9x/20) = 10

⇒ (60x - 8x - 27x) = 10 × 60

⇒ x = 10 × 60/25 = 24 km

**∴ The total distance covered by him is 24 km **