A man travels a certain distance at 12 km/h and returns to the starting point at 9 km/h. The total time taken by him for the entire journey is 
hours. The total distance (in km) covered by him is:
Show answer & explanation
Correct answer: B
Explanation
Correct Answer is option 2 i.e. 24
|
Concept |
Understanding |
Application |
Fair calculation |
|
Time = Distance/Speed |
The man travels a certain distance at 12 km/h and returns to the starting point at 9 km/h Total time = 7/3 hours. Suppose distance (one side) = d km |
d/12 + d/9 = 7/3 7d/36 = 7/3 d = 12 km
Total distance = 24 km |
d/12 + d/9 = 7/3 d[1/12 + 1/9] = 7/3 d[(4 + 3)/36] = 7/3 7d/36 = 7/3 d = 12 |