North then east — Direction Sense Aptitude Question
North then east: A man walks 4 km north, then 3 km east. How far is he from his starting point? Answer and worked solution on CodeKairo.
- Topic: Direction Sense
- Section: Logical Reasoning
- Difficulty: Easy
- Time target: 45 seconds
Question
A man walks 4 km north, then 3 km east. How far is he from his starting point?
Options
- 5 km
- 6 km
- 7 km
- 12 km
Show the answer and the worked solution
Correct answer: A. 5 km
Worked solution
- The displacement is the hypotenuse: √(16 + 9) = √25 = 5 km.
Answer: 5 km.
The idea
Perpendicular legs mean Pythagoras. Watch for the 3-4-5 family, which needs no square root at all.
Shortcut. The straight-line gap must be more than the longer leg (4 km) and less than the two legs added (7 km); only 5 km fits.
Common trap. "7 km" — adding the two legs, which gives the distance walked, not how far he is from the start.