Working together, Joe and Joanne finish a job in 2 hours. How long will it take Jeremy and Joe to finish the job?
(1) Working alone and without breaks Joe takes 5 hours to finish the job, which is 400% as long as the time it takes Jeremy to finish the job.
(2) Working alone and without breaks Joanne takes 10 hours to finish 3 times the job.
Which of the statements is the correct answer?
OA A
Working together, Joe and Joanne
This topic has expert replies
-
- Moderator
- Posts: 7187
- Joined: Thu Sep 07, 2017 4:43 pm
- Followed by:23 members
- GMATGuruNY
- GMAT Instructor
- Posts: 15539
- Joined: Tue May 25, 2010 12:04 pm
- Location: New York, NY
- Thanked: 13060 times
- Followed by:1906 members
- GMAT Score:790
Statement 1:lheiannie07 wrote:Working together, Joe and Joanne finish a job in 2 hours. How long will it take Jeremy and Joe to finish the job?
(1) Working alone and without breaks Joe takes 5 hours to finish the job, which is 400% as long as the time it takes Jeremy to finish the job.
(2) Working alone and without breaks Joanne takes 10 hours to finish 3 times the job.
Since Joe's time of 5 hours is equal to 400% of Jeremy's time, we get:
5 = (400/100)(Jeremy's time)
5 = (4)(Jeremy's time)
5/4 = Jeremy's time.
Case 1: Job = 5 widgets
Since Joe's time = 5 hours, Joe's rate = w/t = 5/5 = 1 widget per hour.
Since Jeremy's time = 5/4 hours, Jeremy's rate = w/t = 5/(5/4) = (5)(4/5) = 4 widgets per hour.
Combined rate for Joe and Jeremy together = 1+4 = 5 widgets per hour.
Since their combined rate = 5 widgets per hour, the time for Joe and Jeremy together to complete the 5-widget job = w/r = 5/5 = 1 hour.
Case 2: Job = 10 widgets
Since Joe's time = 5 hours, Joe's rate = w/t = 10/5 = 2 widgets per hour.
Since Jeremy's time = 5/4 hours, Jeremy's rate = w/t = 10/(5/4) = (10)(4/5) = 8 widgets per hour.
Combined rate for Joe and Jeremy together = 2+8 = 10 widgets per hour.
Since their combined rate = 10 widgets per hour, the time for Joe and Jeremy together to complete the 10-widget job = w/r = 10/10 = 1 hour.
In each case, the time for Joe and Jeremy together is THE SAME (1 hour).
SUFFICIENT.
Statement 2:
No information about Jeremy.
INSUFFICIENT.
The correct answer is A.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
-
- Legendary Member
- Posts: 712
- Joined: Fri Sep 25, 2015 4:39 am
- Thanked: 14 times
- Followed by:5 members
Dear Mitch,GMATGuruNY wrote:Statement 1:lheiannie07 wrote:Working together, Joe and Joanne finish a job in 2 hours. How long will it take Jeremy and Joe to finish the job?
(1) Working alone and without breaks Joe takes 5 hours to finish the job, which is 400% as long as the time it takes Jeremy to finish the job.
(2) Working alone and without breaks Joanne takes 10 hours to finish 3 times the job.
Since Joe's time of 5 hours is equal to 400% of Jeremy's time, we get:
5 = (400/100)(Jeremy's time)
5 = (4)(Jeremy's time)
5/4 = Jeremy's time.
Case 1: Job = 5 widgets
Since Joe's time = 5 hours, Joe's rate = w/t = 5/5 = 1 widget per hour.
Since Jeremy's time = 5/4 hours, Jeremy's rate = w/t = 5/(5/4) = (5)(4/5) = 4 widgets per hour.
Combined rate for Joe and Jeremy together = 1+4 = 5 widgets per hour.
Since their combined rate = 5 widgets per hour, the time for Joe and Jeremy together to complete the 5-widget job = w/r = 5/5 = 1 hour.
Case 2: Job = 10 widgets
Since Joe's time = 5 hours, Joe's rate = w/t = 10/5 = 2 widgets per hour.
Since Jeremy's time = 5/4 hours, Jeremy's rate = w/t = 10/(5/4) = (10)(4/5) = 8 widgets per hour.
Combined rate for Joe and Jeremy together = 2+8 = 10 widgets per hour.
Since their combined rate = 10 widgets per hour, the time for Joe and Jeremy together to complete the 10-widget job = w/r = 10/10 = 1 hour.
In each case, the time for Joe and Jeremy together is THE SAME (1 hour).
SUFFICIENT.
Statement 2:
No information about Jeremy.
INSUFFICIENT.
The correct answer is A.
How come you reach 1 hour in statement A, while its mentioned in the stem that both together will finish a job in 2 hrs, I highlighted it above.
Also I do understand what the question real asks if is every one alone.
Thanks
- GMATGuruNY
- GMAT Instructor
- Posts: 15539
- Joined: Tue May 25, 2010 12:04 pm
- Location: New York, NY
- Thanked: 13060 times
- Followed by:1906 members
- GMAT Score:790
Read carefully.Mo2men wrote:Dear Mitch,
How come you reach 1 hour in statement A, while its mentioned in the stem that both together will finish a job in 2 hrs, I highlighted it above.
Also I do understand what the question real asks if is every one alone.
Thanks
The prompt indicates that the time Joe and JOANNE = 2 hours.
My work in Statement 1 indicates that the time for Joe and JEREMY = 1 hour.
Joe and JOANNE ≠Joe and JEREMY.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
-
- Legendary Member
- Posts: 712
- Joined: Fri Sep 25, 2015 4:39 am
- Thanked: 14 times
- Followed by:5 members
Thanks Mitch,GMATGuruNY wrote:Read carefully.Mo2men wrote:Dear Mitch,
How come you reach 1 hour in statement A, while its mentioned in the stem that both together will finish a job in 2 hrs, I highlighted it above.
Also I do understand what the question real asks if is every one alone.
Thanks
The prompt indicates that the time Joe and JOANNE = 2 hours.
My work in Statement 1 indicates that the time for Joe and JEREMY = 1 hour.
Joe and JOANNE ≠Joe and JEREMY.
I did not take care while I was reading quickly, The names are all close.
-
- Moderator
- Posts: 7187
- Joined: Thu Sep 07, 2017 4:43 pm
- Followed by:23 members
Thanks a lot!GMATGuruNY wrote:Statement 1:lheiannie07 wrote:Working together, Joe and Joanne finish a job in 2 hours. How long will it take Jeremy and Joe to finish the job?
(1) Working alone and without breaks Joe takes 5 hours to finish the job, which is 400% as long as the time it takes Jeremy to finish the job.
(2) Working alone and without breaks Joanne takes 10 hours to finish 3 times the job.
Since Joe's time of 5 hours is equal to 400% of Jeremy's time, we get:
5 = (400/100)(Jeremy's time)
5 = (4)(Jeremy's time)
5/4 = Jeremy's time.
Case 1: Job = 5 widgets
Since Joe's time = 5 hours, Joe's rate = w/t = 5/5 = 1 widget per hour.
Since Jeremy's time = 5/4 hours, Jeremy's rate = w/t = 5/(5/4) = (5)(4/5) = 4 widgets per hour.
Combined rate for Joe and Jeremy together = 1+4 = 5 widgets per hour.
Since their combined rate = 5 widgets per hour, the time for Joe and Jeremy together to complete the 5-widget job = w/r = 5/5 = 1 hour.
Case 2: Job = 10 widgets
Since Joe's time = 5 hours, Joe's rate = w/t = 10/5 = 2 widgets per hour.
Since Jeremy's time = 5/4 hours, Jeremy's rate = w/t = 10/(5/4) = (10)(4/5) = 8 widgets per hour.
Combined rate for Joe and Jeremy together = 2+8 = 10 widgets per hour.
Since their combined rate = 10 widgets per hour, the time for Joe and Jeremy together to complete the 10-widget job = w/r = 10/10 = 1 hour.
In each case, the time for Joe and Jeremy together is THE SAME (1 hour).
SUFFICIENT.
Statement 2:
No information about Jeremy.
INSUFFICIENT.
The correct answer is A.