Aptitude - Time and Distance - Discussion
Discussion Forum : Time and Distance - General Questions (Q.No. 1)
1.
A person crosses a 600 m long street in 5 minutes. What is his speed in km per hour?
Answer: Option
Explanation:
| Speed = |  |
600 |  m/sec. |
| 5 x 60 |
= 2 m/sec.
Converting m/sec to km/hr (see important formulas section)
| = | |
2 x | 18 | |
km/hr |
| 5 |
= 7.2 km/hr.
Discussion:
215 comments Page 22 of 22.
Priya said:
4 years ago
We know that speed= distance/time.
But we can't find the speed for m/min.
So, we can first convert 5 mins to sec. 5*60 = 300 s.
Now we need to find the speed= distance/time= 600/300= 2 m/s.
But we need km/hour. so for converting m/s to km/hour we need to multiply the speed(in m/s) * 18/5 (5/18 for km/hour into m/s).
So, 2*18/5=36/5= 7.2.
But we can't find the speed for m/min.
So, we can first convert 5 mins to sec. 5*60 = 300 s.
Now we need to find the speed= distance/time= 600/300= 2 m/s.
But we need km/hour. so for converting m/s to km/hour we need to multiply the speed(in m/s) * 18/5 (5/18 for km/hour into m/s).
So, 2*18/5=36/5= 7.2.
Umang Joshi said:
4 years ago
Speed = distance*time guys now,
Speed = 5min OR 5*60= 300 second
Distance = 600m.
By using above formula;
s = D/T.
S = 600/5 * 60.
= 2m/sec.
Converting it into km/h to m/sec we do 5/18 which is 1000/3600,
For converting m/s into km/hour use 18/5 -----> (1)
Now using (1).
18/5*2 = 7.2 km/hour answer which is option (B)
hope you all got it.
Speed = 5min OR 5*60= 300 second
Distance = 600m.
By using above formula;
s = D/T.
S = 600/5 * 60.
= 2m/sec.
Converting it into km/h to m/sec we do 5/18 which is 1000/3600,
For converting m/s into km/hour use 18/5 -----> (1)
Now using (1).
18/5*2 = 7.2 km/hour answer which is option (B)
hope you all got it.
Akuymakan said:
4 years ago
I don't get it. Please explain in detail.
Vishalini said:
4 years ago
Thank you @Mallikarjun.
DRIBAREO DOREEN said:
15 hours ago
How does the 18 come about? Please explain.
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