NEW HERE? LEARN MORE
closeclose
Last visit was: 26 Apr 2024, 13:17 It is currently 26 Apr 2024, 13:17
Decision Tracker
My Rewards
New posts
New comers' posts

Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

A and B run a race, in the same direction on a circular track of 100 m

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92948
Own Kudos [?]: 619228 [22]
Given Kudos: 81609
Send PM
CAT Tests Forum Quiz Mode
A and B run a race, in the same direction on a circular track of 100 m [#permalink] New post   06 Jan 2020, 08:08
22
Bookmarks
Expert Reply
00:00
A
B
C
D
E

Difficulty:

75% (hard)

Question Stats:

53% (02:14) correct 47% (02:24) wrong based on 148 sessions
Hide Show timer Statistics
A and B run a race, in the same direction on a circular track of 100 meters. If the race was of 2000 meters and the ratio of speeds of A and B was 5 : 3, find the number of times the two meet?

A. 4
B. 5
C. 6
D. 7
E. 8
ShowHide Answer
Official Answer
E
Most Helpful Reply
avatar
B
DevangiK
Intern
Intern
Joined: 25 Nov 2019
Posts: 10
Own Kudos [?]: 17 [6]
Given Kudos: 3
Send PM
Re: A and B run a race, in the same direction on a circular track of 100 m [#permalink] New post   08 Jan 2020, 02:05
5
Kudos
1
Bookmarks
Bunuel wrote:
A and B run a race, in the same direction on a circular track of 100 meters. If the race was of 2000 meters and the ratio of speeds of A and B was 5 : 3, find the number of times the two meet?

A. 4
B. 5
C. 6
D. 7
E. 8



Given,
The length of circular track = 100 mtrs.
Length of the race = 2000 mtrs.
Total rounds taken by the athletes to complete the race = 2000/100 = 20 rounds

Now,ratio of speed of the two athletes = 5:3
We calculate time, using the relative speed formula,

Relative Speed = Relative Distance / Time


Relative Speed = 2 (5-3)
Relative Distance = 100 mtrs.(distance of the circular track)

So, Time = 100/2 = 50 sec

Now, the distance covered by faster athlete in 50 sec = 50*5
After running 250 mtrs. both athletes will cross eachother.

Thus, In a race of 2000 mtrs after every 250 mtrs they will cross eachother, which means, they will cross eachother 2000/250 = 8 times.

The correct answer is option E.
General Discussion
avatar
B
Stonely
Intern
Intern
Joined: 25 Nov 2019
Posts: 34
Own Kudos [?]: 29 [2]
Given Kudos: 7
Send PM
Re: A and B run a race, in the same direction on a circular track of 100 m [#permalink] New post   06 Jan 2020, 09:09
2
Kudos
let's assume A runs 10m/s that means B runs 6m/s so we know it takes A 200 sec to finish the course and in 200 seconds B runs 1200m in my mind that means B has 8 laps remaining or they met 8 times.
avatar
S
JohnWidestone
Intern
Intern
Joined: 10 Sep 2019
Posts: 42
Own Kudos [?]: 63 [0]
Given Kudos: 33
Location: Switzerland
Concentration: Strategy, Economics
GPA: 3.1
Send PM
Re: A and B run a race, in the same direction on a circular track of 100 m [#permalink] New post   10 Jan 2020, 15:37
Bunuel wrote:
A and B run a race, in the same direction on a circular track of 100 meters. If the race was of 2000 meters and the ratio of speeds of A and B was 5 : 3, find the number of times the two meet?

A. 4
B. 5
C. 6
D. 7
E. 8




Given the length of the race A runs 20 times the circular track to finish. Lets assume that A runs at a rate of 100m/min, thus B runs at a rate of 60m/min. Starting at the same point the difference is 40m/min. Therefore, it takes A 2.5 laps to overtake B. 20 laps in total divided by 2.5 gives us 4.

IMO: A
User avatar
L
Kinshook
GMAT Club Legend
GMAT Club Legend
Joined: 03 Jun 2019
Posts: 5344
Own Kudos [?]: 3968 [3]
Given Kudos: 160
Location: India
Schools: HBS '22 CBS '22 Wharton '22
GMAT 1: 690 Q50 V34
WE:Engineering (Transportation)
Send PM
Reviews Badge
Re: A and B run a race, in the same direction on a circular track of 100 m [#permalink] New post   31 Mar 2020, 08:57
3
Kudos
Bunuel wrote:
A and B run a race, in the same direction on a circular track of 100 meters. If the race was of 2000 meters and the ratio of speeds of A and B was 5 : 3, find the number of times the two meet?

A. 4
B. 5
C. 6
D. 7
E. 8


Given: A and B run a race, in the same direction on a circular track of 100 meters.

Asked: If the race was of 2000 meters and the ratio of speeds of A and B was 5 : 3, find the number of times the two meet?

Let the speeds of A and B be 5x & 3x m/s respectively

Time after they first met = 100/2x = 50/xseconds

Race is completed in = 2000/5x = 400/x seconds

Number of time they met = (400/x)/(50/x) = 8 times

IMO E
User avatar
L
Archit3110
GMAT Club Legend
GMAT Club Legend
Joined: 18 Aug 2017
Status:You learn more from failure than from success.
Posts: 8020
Own Kudos [?]: 4098 [1]
Given Kudos: 242
Location: India
Concentration: Sustainability, Marketing
GMAT Focus 1:
545 Q79 V79 DI73
GPA: 4
WE:Marketing (Energy and Utilities)
Send PM
GMAT ToolKit User CAT Tests
Re: A and B run a race, in the same direction on a circular track of 100 m [#permalink] New post   13 Jul 2021, 01:08
1
Kudos
total laps in the race 2000/100 ; 20
since both are running in same direction so relative speed 5-3 ; 2
time taken per lap ; 100/2 ; 50 sec
distance A travels in 50 sec ; 50*5 ;250 mtrs
total times they meet 2000/250; 8
option E

Bunuel wrote:
A and B run a race, in the same direction on a circular track of 100 meters. If the race was of 2000 meters and the ratio of speeds of A and B was 5 : 3, find the number of times the two meet?

A. 4
B. 5
C. 6
D. 7
E. 8
User avatar
G
sting8
Current Student
Joined: 03 Dec 2020
Posts: 60
Own Kudos [?]: 94 [2]
Given Kudos: 217
Location: India
Debrief: https://gmatclub.com/forum/740-v40-q50-second-attempt-self-preparation-375379.html
Concentration: Technology, Strategy
Schools: ISB '23 (A) Tepper '24 (WL) Ross '24 (D)
GMAT 1: 720 Q49 V39
GMAT 2: 740 Q50 V40
WE:Engineering (Computer Hardware)
Send PM
A and B run a race, in the same direction on a circular track of 100 m [#permalink] New post   13 Aug 2021, 00:50
1
Kudos
1
Bookmarks
There are (5-3) = 2 meeting points.
Since, faster person will complete the race first. We should look at the problem from his perspective.

No. of laps for A = 2000/100 = 20

When A completes 5 laps, they meet 2 times
So, when A completes 20 laps, they meet 8 times.


Similarly, if A and B were running in opposite directions,
there would be 8 meeting points.

When A covers 5 laps, they meet 8 times
so, when A covers 20 laps, they meet 32 times
User avatar
bumpbot
Non-Human User
Joined: 09 Sep 2013
Posts: 32688
Own Kudos [?]: 822 [0]
Given Kudos: 0
Send PM
Re: A and B run a race, in the same direction on a circular track of 100 m [#permalink] New post   06 May 2023, 20:45
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
GMAT Club Bot
gmatclubot
Re: A and B run a race, in the same direction on a circular track of 100 m [#permalink]
06 May 2023, 20:45
Moderators:
Bunuel
Math Expert
92948 posts
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions