Walking one way, riding the other — Aptitude Question
Walking one way, riding the other: A man walks to a place and rides back, taking 5 hours 45 minutes in all. Answer and worked solution on CodeKairo.
- Topic: Time, Speed & Distance
- Section: Quantitative Aptitude
- Difficulty: Hard
- Time target: 105 seconds
Question
A man walks to a place and rides back, taking 5 hours 45 minutes in all. He could have ridden both ways in 4 hours. How long would he take to walk both ways?
Options
- 6 h
- 6 h 30 min
- 7 h
- 7 h 30 min
Show the answer and the worked solution
Correct answer: D. 7 h 30 min
Worked solution
- Riding both ways = 4 h, so one ride = 2 h.
- Walk + ride = 5 h 45 min, so one walk = 5 h 45 min − 2 h = 3 h 45 min.
- Walking both ways = 2 × 3 h 45 min = 7 h 30 min.
Answer: 7 h 30 min.
The idea
Halve the both-ways time to get one leg, subtract to get the other leg, then double it. No speeds or distances are ever needed.
Shortcut. Walk both ways = 2 × (walk + ride) − (ride both) = 11 h 30 min − 4 h = 7 h 30 min.
Common trap. 7 h — treating 5 h 45 min as 5.45 h: 2 × 5.45 − 4 = 6.9 h, which rounds to 7; 45 minutes is 0.75 h, giving exactly 7.5 h.