A man is delayed in reaching his workplace by 30 minutes due to bad traffic as he can drive at
9
7
of his usual speed. What is his usual time (in hours and minutes) of travel?
- A2 hours 10 minutes
- B1 hour 45 minutes
- C2 hours 15 minutes
- D1 hour 30 minutes
Solution & Step-by-step Explanation
Since distance to the workplace is constant, speed and time are inversely proportional.
Ratio of Speed (Usual : New)=9:7
Ratio of Time (Usual : New)=7:9
Let the usual time be 7x and the new time be 9x.
The difference in time is given as 30 minutes:
9x−7x=30 minutes
2x=30⟹x=15 minutes
Usual time of travel:
Usual Time=7x=7×15=105 minutes
105 minutes=1 hour 45 minutes
Ratio of Speed (Usual : New)=9:7
Ratio of Time (Usual : New)=7:9
Let the usual time be 7x and the new time be 9x.
The difference in time is given as 30 minutes:
9x−7x=30 minutes
2x=30⟹x=15 minutes
Usual time of travel:
Usual Time=7x=7×15=105 minutes
105 minutes=1 hour 45 minutes