Question

A driver completes his journey without stopping is 10 hrs. If he travelled 8 km an hour faster, he would have done the journey in 6 hours 40 min. Find his slower speed.
1. 16 km
2. 61 km
3. 26 km
4. 62 km

Answer 1

Correct Answer - Option 1 : 16 km

Given∶

Time taken to complete his journey = 10 hrs

Speed increased from his used speed = 8 km/hr

Time taken to finish the journey with increased speed = 6 hours 40 min = 20 / 3 hours

Formula Used∶

Distance = Speed / Time

Calculation∶

Let the faster speed be V and the slower speed be v

Distance covered with normal speed = Distance covered with faster speed.

⇒ v × Time taken = V × Time taken

⇒ v × 10 = (v + 8) × (20 / 3)

⇒ 3v = 2v + 16

⇒ 3v – 2v = 16

⇒ v = 16 km/h

∴ The slower speed is 16 km/h.