A driver drives a car at a uniform speed of 60 km/h and reaches the 330 km destination by 30 min late. To reach on time, the % increase in speed will be:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 10%.
Given:
A driver drives a car at a uniform speed of 60 km/h and reaches the 330 km destination by 30 min late
Formula used:
Time = Distance/speed ---- (1)
Calculations:
Time taken to cover 330 km = 330/60 = 5 hour 30 mins
If he was 30 mins late, required time taken = 5.5 - 0.5 = 5 hours
Required time = 330/5 = 66 km/h
Required percentage increase in speed = [(66 - 60)/60] × 100 = 10%