Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2308:00 PM PDT
-09:00 PM PDT
Video explanations + diagnosis of 10 weakest areas + 150+ short videos + study plan!
Apr 2301:30 AM EDT
-02:30 AM EDT
Struggling with GMAT Verbal as a non-native speaker? Harsh improved his score from 595 to 695 in just 45 days—and scored a 99 %ile in Verbal (V88)! Learn how smart strategy, clarity, and guided prep helped him gain 100 points.
Apr 2512:30 AM EDT
-01:30 AM EDT
At one point, she believed GMAT wasn’t for her. After scoring 595, self-doubt crept in and she questioned her potential. But instead of quitting, she made the right strategic changes. The result? A remarkable comeback to 695. Check out how Saakshi did it.
Apr 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
23 Oct 2013, 11:50
Kudos
Bookmarks
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
95%
(hard)
Question Stats:
54% (03:39) correct
46%
(03:41)
wrong
based on 93
sessions
History
Date
Time
Result
Not Attempted Yet
P,Q and R can do a piece of work in 4,6 and 12 days working 12 hrs a day.On each day p starts the work and works for 8 hrs then q works for 8 hrs and then r works for 8 hrs.in the same way they continue until p leaves after 2 days. then q and r work alternately for 8 hrs each till work is completed , in how many days is the work completed.
1) 10/3 days
2) 7/2 days
3) 11/3 days
4) 15/4 days
5) 21/4 days
1) 10/3 days
2) 7/2 days
3) 11/3 days
4) 15/4 days
5) 21/4 days
ssfuturemba
Joined: 01 Aug 2013
Last visit: 20 Nov 2013
Posts: 8
Location: United States
Concentration: Operations, International Business
GMAT 1: 710 Q47 V41
GPA: 3.65
GMAT 1: 710 Q47 V41
Posts: 8
23 Oct 2013, 13:03
Kudos
Bookmarks
I did this by adding each day up day-by-day
1. We have P doing the work in 4 (half) days, which means the work can be done in 2 full days, or 1/2 work/day
2. Q = 6(half) = 3 full = 1/3 work/day
3. R = 12(half) = 6 full = 1/6 work/day
So let's calculate the first day:
8 hours by P (1/3 of a day) = 1/3*1/2 = 1/6
8 hours by Q = ----------------- 1/3*1/3 = 1/9
8 hours by R ==-----------------1/3*1/6 = 1/18
Total per day with P,Q,and R is 6/18 = 1/3
The second day is the same, so after 2 days we have 2/3 completed.
The third day is just Q and R, so the first 8 hours will be Q (1/9), then R (1/18), then Q again (1/9)
Now that gives us 5/18, which when added to the first 2 days' total gives us 17/18 after 3 days
The fourth day starts with R, since Q finished day 3, and just needs to finish 1/18 of the total to complete the work, which we know takes R 8 hours.
Therefore, it takes 3 days 8 hours which can be confusingly written as 10/3 days.
A is the answer
1. We have P doing the work in 4 (half) days, which means the work can be done in 2 full days, or 1/2 work/day
2. Q = 6(half) = 3 full = 1/3 work/day
3. R = 12(half) = 6 full = 1/6 work/day
So let's calculate the first day:
8 hours by P (1/3 of a day) = 1/3*1/2 = 1/6
8 hours by Q = ----------------- 1/3*1/3 = 1/9
8 hours by R ==-----------------1/3*1/6 = 1/18
Total per day with P,Q,and R is 6/18 = 1/3
The second day is the same, so after 2 days we have 2/3 completed.
The third day is just Q and R, so the first 8 hours will be Q (1/9), then R (1/18), then Q again (1/9)
Now that gives us 5/18, which when added to the first 2 days' total gives us 17/18 after 3 days
The fourth day starts with R, since Q finished day 3, and just needs to finish 1/18 of the total to complete the work, which we know takes R 8 hours.
Therefore, it takes 3 days 8 hours which can be confusingly written as 10/3 days.
A is the answer
21 Jun 2019, 18:59
Kudos
Bookmarks
P takes 4 days working 12 hrs/day to complete the job i.e. he takes 48 man-hours to complete the job.
Q takes 6 days working 12 hrs/day to complete the job i.e. he takes 72 man-hours to complete the job.
R takes 12 days working 12 hrs/day to complete the job i.e. he takes 144 man-hours to complete the job.
Taking the LCM of the total man-hours, let us say that the total work was 144 units.
If P completes 144 units in 48 hours, then P completes 24 units in 8 hours (by unitary method).
If Q completes 144 units in 72 hours, then Q completes 16 units in 8 hours (by unitary method).
If R completes 144 units in 144 hours, then R completes 8 units in 8 hours (by unitary method).
So on days 1 and 2, we have
First 8 hours (P) - 24 units
Next 8 hours (Q) - 16 units
Last 8 hours (R) - 8 units
Total - 48 units per day, so 96 units completed in 2 days.
Now, P leaves after day 2 while Q and R continue working alternatively. So on day 3, we have
First 8 hours (Q) - 16 units
Next 8 hours (R) - 8 units
Last 8 hours (Q) - 16 units
Total - 40 units per day
So, we have 136 units completed in 3 complete days and require 8 more hours to complete the task.
On day 4, resuming from who did the work last, we have
First 8 hours (R) - 8 units
So we have completed the task and taken 3 complete days and 8/24 => 1/3rd of the 4th day.
So total days taken => 3 + 1/3 = 10/3 days. Hence, Option A is the right choice.
Q takes 6 days working 12 hrs/day to complete the job i.e. he takes 72 man-hours to complete the job.
R takes 12 days working 12 hrs/day to complete the job i.e. he takes 144 man-hours to complete the job.
Taking the LCM of the total man-hours, let us say that the total work was 144 units.
If P completes 144 units in 48 hours, then P completes 24 units in 8 hours (by unitary method).
If Q completes 144 units in 72 hours, then Q completes 16 units in 8 hours (by unitary method).
If R completes 144 units in 144 hours, then R completes 8 units in 8 hours (by unitary method).
So on days 1 and 2, we have
First 8 hours (P) - 24 units
Next 8 hours (Q) - 16 units
Last 8 hours (R) - 8 units
Total - 48 units per day, so 96 units completed in 2 days.
Now, P leaves after day 2 while Q and R continue working alternatively. So on day 3, we have
First 8 hours (Q) - 16 units
Next 8 hours (R) - 8 units
Last 8 hours (Q) - 16 units
Total - 40 units per day
So, we have 136 units completed in 3 complete days and require 8 more hours to complete the task.
On day 4, resuming from who did the work last, we have
First 8 hours (R) - 8 units
So we have completed the task and taken 3 complete days and 8/24 => 1/3rd of the 4th day.
So total days taken => 3 + 1/3 = 10/3 days. Hence, Option A is the right choice.
