A man walks 8 km towards South and then turns left. After walking 6 km, he…
2017
A man walks 8 km towards South and then turns left. After walking 6 km, he turns partially left in such a way that while walking straight he reaches his starting point. The total distance travelled by him was:
- A.
10 km
- B.
19 km
- C.
24 km
- D.
30 km
Attempted by 138 students.
Show answer & explanation
Correct answer: C
Key idea: use the Pythagorean theorem to find the straight-line return distance and then sum all legs.
Step 1: Track the position after each move. Start at the origin. After walking 8 km south the position is 8 km south of the start. After then turning left and walking 6 km, the position is 6 km east and 8 km south of the start.
Step 2: The return from this point to the start forms a right triangle with legs 6 km and 8 km, so the return distance is sqrt(6^2 + 8^2) = 10 km.
Step 3: Add all travelled distances: 8 km + 6 km + 10 km = 24 km.
Final answer: 24 km