-
A person covers 10 kms at 4 km per hr. and then further 21 kms at 6 km per hr. Find his average speed for whole journey.
-
-
5 1 kmph 3 -
5 1 kmph 6 -
5 1 kmph 2 -
4 1 kmph 2
-
Correct Option: B
Case I.
Distance = 10 kms
Speed = 4 km/hr.
| ∴ Time taken (t2) = | = | hrs. | ||
| 6 | 2 |
| Total time taken = | + | ||
| 2 | 2 |
| = | = 6 hrs. | |
| 2 |
Total distance covered
= 10 + 21 = 31 kms
| ∴ Average Speed = | |
| Total time |
| = | km per hr. | |
| 6 |
| = 5 | km per hr. | |
| 6 |
