Time and Distance Questions Answers
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22. A thief is noticed by a policeman from a distance of 200 m. The thief starts running and the policeman chases him. The thief and the policeman run at the rate of 10 km and 11 km per hour respectively. What is the distance between them after 6 minutes ?
- 50 meter
- 100 meter
- 110 meter
- None of above
Answer And Explanation
Answer: Option B
Explanation:
Relative speed of the thief and policeman = (11 – 10) km/hr = 1 km/hr
Distance covered in 6 minutes =
\begin{aligned}
\frac{1}{60}*6 = \frac{1}{10} \\
= 100 meters
\end{aligned}
So distance between them after 6 minutes = 200 - 100
= 100 meters -
23. The ratio between the speeds of two trains is 7: 8. If the second train runs 400 kms in 4 hours, then the speed of the first train is ?
- 83.5 km/hr
- 84.5 km/hr
- 86.5 km/hr
- 87.5 km/hr
Answer And Explanation
Answer: Option D
Explanation:
Let the speeds of two trains be 7X and 8X km/hr.
\begin{aligned}
8X = \frac{400}{4} \\
=> X = 12.5 Km/hr
\end{aligned}
So speed of first train is 12.5*7 = 87.5 km/hr -
24. Ram and Sham are running a race, Ram runs 25% faster than Sham and is able to allow Sham a lead of 7 meters to end a race in dead heat. Find the distance of the race.
- 32 meters
- 35 meters
- 39 meters
- 40.5 meters
Answer And Explanation
Answer: Option B
Explanation:
Important to Note first - Dead Head means - run or finish a race at exactly level or at same time.
From question it is clear that Ram runs faster than Sham by 25%,
So if Sham runs 100 meter in a given time then Ram will run 125 meter in that time.
So if Sham runs 4 meter then Ram will run 5 meter in given time (divide both by 25)
=> Ram can give Sham a lead of 1 meter in 5 meter race to finish race in dead heat.
Ratio of length of start given : length of race :: 1 : 5
As per question, start was given of 7 meter, So,
Length of race was 7 * 5 = 35.