Last visit was: 24 Apr 2026, 08:31 It is currently 24 Apr 2026, 08:31
Home
Messages
Tests
Schools
Events
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
Back to Forum
Create Topic
User avatar
kritisachan
User avatar
Joined: 10 Jun 2021
Last visit: 26 Jul 2024
Posts: 10
Own Kudos:
23
 [17]
Given Kudos: 41
Location: India
Posts: 10
Kudos: 23
 [17]
At 6am, just after the racing club opens, Martha begins to jog around Updated on: 26 Jun 2023, 01:00
Originally posted by kritisachan on 26 Jun 2023, 00:59.
Last edited by Bunuel on 26 Jun 2023, 01:00, edited 1 time in total.
Renamed the topic.
3
Kudos
Add Kudos
14
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

65% (hard)

Question Stats:

64% (03:00) correct 36% (03:17) wrong based on 117 sessions

History

Date
Time
Result
Not Attempted Yet
At 6am, just after the racing club opens, Martha begins to jog around a 600-metre racing track at a steady pace of 6 kilometres an hour. Saad arrives later and only begins running at 6:30am, maintaining a steady pace of 8 kilometres per hour. If they both started their runs at the same point, and continue to run until at least 9:30am, by what time has Saad done five more laps around the track than Martha?

A. 7:30am
B. 8:10am
C. 8:30am
D. 9:10am
E. 9:30am

Posted from my mobile device
ShowHide Answer
Official Answer
E
User avatar
gmatophobia
User avatar
Quant Chat Moderator
Joined: 22 Dec 2016
Last visit: 19 Apr 2026
Posts: 3,173
Own Kudos:
11,461
 [3]
Given Kudos: 1,862
Location: India
Concentration: Strategy, Leadership
Posts: 3,173
Kudos: 11,461
 [3]
At 6am, just after the racing club opens, Martha begins to jog around 26 Jun 2023, 04:50
2
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
kritisachan
At 6am, just after the racing club opens, Martha begins to jog around a 600-metre racing track at a steady pace of 6 kilometres an hour. Saad arrives later and only begins running at 6:30am, maintaining a steady pace of 8 kilometres per hour. If they both started their runs at the same point, and continue to run until at least 9:30am, by what time has Saad done five more laps around the track than Martha?

A. 7:30am
B. 8:10am
C. 8:30am
D. 9:10am
E. 9:30am

Posted from my mobile device
Show more

  • Speed of Martha = 6000m / hr
  • Speed of Saad = 8000m / hr

By 6:30 am, Martha covers 3000 m.

Number of laps completed by Martha = \(\frac{3000}{600}\) = 5 laps.

At 6:30 am, both Martha and Saad are the starting point. Saad has to complete at least 10 laps.

Distance to be covered by Saad = 10 * 600 m

Relative Speed = 8000 - 6000 = 2000 m/hr

Time taken = \(\frac{6000}{2000}\) = 3 hours

Hence, Saad will complete 10 laps at 9:30 am.

Option E
User avatar
Crater
User avatar
Joined: 14 May 2023
Last visit: 26 Nov 2024
Posts: 53
Own Kudos:
78
 [1]
Given Kudos: 9
Location: India
Posts: 53
Kudos: 78
 [1]
At 6am, just after the racing club opens, Martha begins to jog around 02 Jul 2023, 18:27
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
kritisachan
At 6am, just after the racing club opens, Martha begins to jog around a 600-metre racing track at a steady pace of 6 kilometres an hour. Saad arrives later and only begins running at 6:30am, maintaining a steady pace of 8 kilometres per hour. If they both started their runs at the same point, and continue to run until at least 9:30am, by what time has Saad done five more laps around the track than Martha?
Show more

Martha
0.6 km at 6 km/h
1 round in 6 min
10 rounds in 60 min

Also Martha has a head start of 5 rounds (Started at 6:00)

Saad
0.6 km at 8 km/h
1 round in 4.5 min
40/3 rounds in 60 min

\((40/3-10)x-5=5\)
\(x=3\) hours

Hence, Saad would have done 5 more rounds than Martha at 9:30 AM.

Option (E)
User avatar
AK1995
User avatar
Joined: 14 Apr 2023
Last visit: 22 Feb 2026
Posts: 86
Own Kudos:
39
Given Kudos: 37
Schools: IIM (WL)
Schools: IIM (WL)
Posts: 86
Kudos: 39
At 6am, just after the racing club opens, Martha begins to jog around 04 Jul 2023, 19:18
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Martha ran for 3.5 hours at a speed of 6 km/h. So she covered a total distance of 21 km = 35 laps.
Saad ran for 3 hours at a speed of 8 km/h. So he covered a total distance of 24 km = 40 laps.

Since Saad is ahead of Martha by 5 laps at the end of both their runs, answer is 9:30.

Of course this approach worked better because the question exactly asks 5 laps. Had it asked when Saad would be 2 or 3 laps ahead, then any of the above methods would be better.
User avatar
SaquibHGMATWhiz
User avatar
GMATWhiz Representative
Joined: 23 May 2022
Last visit: 12 Jun 2024
Posts: 623
Own Kudos:
777
 [1]
Given Kudos: 6
Location: India
GMAT 1: 760 Q51 V40
Expert
Expert reply
GMAT 1: 760 Q51 V40
Posts: 623
Kudos: 777
 [1]
At 6am, just after the racing club opens, Martha begins to jog around 06 Jul 2023, 22:26
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
kritisachan
At 6am, just after the racing club opens, Martha begins to jog around a 600-metre racing track at a steady pace of 6 kilometres an hour. Saad arrives later and only begins running at 6:30am, maintaining a steady pace of 8 kilometres per hour. If they both started their runs at the same point, and continue to run until at least 9:30am, by what time has Saad done five more laps around the track than Martha?

A. 7:30am
B. 8:10am
C. 8:30am
D. 9:10am
E. 9:30am
Show more

Solution:

  • Let us look at this question from a different perspective and use the options to our advantage.
  • Martha runs at 6 kmph which means \(\frac{6000}{600}=\) 10 laps in 1 hour
  • Saad runs at 8 kmph which means \(\frac{8000}{600}=\) 13.33 laps in 1 hour

  • It is clear that at 6:30am -
    • Martha = 5 laps
    • Saad = 0 laps

  • 1 hour later at 7:30am -
    • Martha = 5 + 10 = 15 laps
    • Saad = 0 + 13.33 = 13.33 laps
  • Saad is behind

  • 2 hours later at 8:30am -
    • Martha = 15 + 10 = 25 laps
    • Saad = 13.33 + 13.33 = 26.66 laps
  • Saad is 1.66 laps ahead

  • 3 hours later at 9:30am -
    • Martha = 25 + 10 = 35 laps
    • Saad = 26.66 + 13.33 = 40 laps
  • Saad is 5 laps ahead

Hence the right answer is Option E
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,974
Own Kudos:
1,117
Posts: 38,974
Kudos: 1,117
At 6am, just after the racing club opens, Martha begins to jog around 20 Aug 2024, 20:14
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Bunuel
Math Expert
109814 posts
Krunaal
Tuck School Moderator
853 posts