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 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 2601:30 AM EDT
-02:30 AM EDT
Learn how Keshav, a Chartered Accountant, scored an impressive 705 on GMAT in just 30 days with GMATWhiz's expert guidance. In this video, he shares preparation tips and strategies that worked for him, including the mock, time management, and more.
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.
May 0111:00 AM PDT
-12:00 PM PDT
Free- full-length test + 15 concept videos + 150+ short videos + study plan!
04 Feb 2021, 04:15
Kudos
Bookmarks
B
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:
58% (03:20) correct
42%
(03:23)
wrong
based on 149
sessions
History
Date
Time
Result
Not Attempted Yet
Taps A and C can fill a tank in 5 and 20 hrs respectively. Taps B and D can drain a full tank in 10 and 40 hrs. respectively. If A, B, C and D are opened in a gap of 2 hrs. in that order the tank gets full in :
A. 28/5 hrs
B. 34/5 hrs
C. 36/5 hrs
D. 38/5 hrs
E. 39/5 hrs
A. 28/5 hrs
B. 34/5 hrs
C. 36/5 hrs
D. 38/5 hrs
E. 39/5 hrs
04 Feb 2021, 04:26
Kudos
Bookmarks
Bunuel
Let, tank capacity = LCM (5, 20, 10 and 40) units = 40 units
(Inlet does +ve work while outlet does -ve work)
Work done by Tap A in 1 hour \(= \frac{40}{5} = +8\) Units
Work done by Tap C in 1 hour \(= \frac{40}{20} = +2\) Units
Work done by Tap B in 1 hour \(= \frac{40}{10} = -4\) Units
Work done by Tap D in 1 hour \(= \frac{40}{40} = -1\) Units
Let, A works for T hours
then B works for (T-2) hours
then C works for (T-4) hours
then D works for (T-6) hours
Total work of A, B, C and D = 8T - 4(T-2) + 2*(T-4) - 1*(T-6) = 40
i.e. 8T - 4(T-2) + 2*(T-4) - 1*(T-6) = 40
i.e. 5T +6 = 40
i.e. T = 34/5 Hours = 6.8 hours
Answer: Option B
General Discussion
18 Feb 2021, 14:33
Kudos
Bookmarks
Bunuel
Solution:
The rates for taps A, B, C, and D are 1/5, 1/10, 1/20, and 1/40, respectively.
We can let x be the number of hours tap A is opened (notice that this is also the number of hours it takes to fill the tank completely since tap A is opened for the entire duration of the tank’s filling). Then tap B is opened for (x - 2) hours, tap C for (x - 4) hours, and tap D for (x - 6) hours. We can create the equation:
(1/5)(x) - (1/10)(x - 2) + (1/20)(x - 4) - (1/40)(x - 6) = 1
Multiplying the equation by 40, we have:
8x - 4x + 8 + 2x - 8 - x + 6 = 40
5x = 34
x = 34/5
Answer: B
