Question

A car covered 150 km in 5 hours. If it travels at one-third its usual speed, then how much more time will it take to cover the same distance?

• A. 12 hours
• B. 14 hours
• C. 10 hours
• D. 8 hours

Answer 1

Answer:

C. 10 hours

Solution: Given: Distance covered by car = 150 km Time taken by the car = 5 hours Formula used: Distance = Speed × Time Calculation: Speed of car = 150/5 ⇒ Speed of car = 30 km/h According to the question, if he travels at 1/3rd of its usual speed then ⇒ Speed = 30/3 km/h ⇒ Speed = 10 km/h ⇒ Time taken to travel 150 km at reduced speed = 150/10 hours ⇒ Time taken to travel 150 km at reduced speed = 15 hours ⇒ Increase in time = (15 – 5) hours ⇒ Increase in time 10 hours ∴ It will take 10 hours more to cover same distance if speed gets reduced to 1/3rd its usual speed. Shortcut Trick As per the question, Speed ratio = 3:1 Time ratio = 1:3 Given 1 unit = 5 hour so 3 unit = 15 hour Increase in time = (15 – 5) hours = 10 hours