-
Shard cover two-third of a certain distance at 4 km/hr and the remaining at 5 km/hr. If he takes 42 minutes in all, the distance is ?
-
- 2.5 km.
- 4.6 km.
- 4 km.
- 3 km.
Correct Option: D
Let total distance be y km.
Then , (2y / 3) / 4 + ( y / 3) / 5 = 42/60
⇒ y/6 + y/ 15 = 7/10
⇒ 5y + 2y = 21
∴ y = 3
∴ Required distance = 3 km.