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?
3.6
7.2
8.4
10
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:
209 comments Page 21 of 21.

Mao said:   5 years ago
The answer is 7.2. Agree with the given answer.

Adrija Das said:   5 years ago
Why divided by 60?

If we want to convert minute to seconds then don't we have to multiply the minute * 60? Please anyone explain.

Pio Myria said:   5 years ago
Step-1: We that distance =600m,time is 5min.
Step-2: Formula=speed=distance/time,
600m/5* 60 = 2m/s.

Step -3 : convert m/s to km/hr.
2*18/5=7.2km/hr ans.

Yashwanth Reddy Chamala said:   5 years ago
Street lenght= 600m.
Time is taken by the person to Cross the street= 5min,
600m/5min*(3/50)=7.2km/hr,
Speed of the person in km=7.2km/hr.
1m/min=3/50km/hr.

Minnal said:   4 years ago
Street lenght = 600m.
Time is taken by the person to Cross the street = 5min,
600m/5min *(3/50) = 7.2km/hr,
Speed of the person in km =7.2km/hr.
1m/min = 3/50km/hr.

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.

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.

Akuymakan said:   4 years ago
I don't get it. Please explain in detail.

Vishalini said:   4 years ago
Thank you @Mallikarjun.


Post your comments here:

Your comments will be displayed after verification.