Last visit was: 22 Apr 2026, 10:51 It is currently 22 Apr 2026, 10:51
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.
Close
Request Expert Reply
Confirm Cancel
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 22 Apr 2026
Posts: 109,748
Own Kudos:
810,639
 [9]
Given Kudos: 105,821
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,748
Kudos: 810,639
 [9]
Kudos
Add Kudos
9
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
ElninoEffect
Joined: 07 Apr 2020
Last visit: 06 Mar 2026
Posts: 314
Own Kudos:
501
 [6]
Given Kudos: 72
Location: India
Concentration: Strategy, Technology
WE:Engineering (Computer Software)
Posts: 314
Kudos: 501
 [6]
4
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
General Discussion
User avatar
NoraUnoSama
Joined: 06 Jan 2023
Last visit: 25 Sep 2023
Posts: 15
Own Kudos:
11
 [3]
Given Kudos: 16
Posts: 15
Kudos: 11
 [3]
3
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
NoraUnoSama
Joined: 06 Jan 2023
Last visit: 25 Sep 2023
Posts: 15
Own Kudos:
11
 [4]
Given Kudos: 16
Posts: 15
Kudos: 11
 [4]
4
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Time = Work / Rate.

A is the rate of the first pipe and hence 0.5A that of the second.

A + 0.5A = 1.5A

Hence 1/1.5A = 2 => 3A = 1 => A = 1/3.

The time for the first pipe is 1/(1/3) = 3 Hours.
User avatar
Aryan19852
Joined: 31 Oct 2023
Last visit: 07 Feb 2025
Posts: 32
Own Kudos:
Given Kudos: 107
Products:
Posts: 32
Kudos: 11
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Assume capacity is 6 liters x+2x fill up in 2 hrs so x alone would fill in 6 hrs half the bucket 3 hrs
User avatar
finisher009
Joined: 10 Jun 2025
Last visit: 22 Jan 2026
Posts: 49
Own Kudos:
Given Kudos: 54
GMAT Focus 1: 625 Q82 V83 DI78
GMAT Focus 1: 625 Q82 V83 DI78
Posts: 49
Kudos: 9
Kudos
Add Kudos
Bookmarks
Bookmark this Post
GMAT Hack: Solve with Logic & Ratios

The key is to think in terms of ratios and avoid setting up complex algebraic fractions.

1. Rates vs. Times: The emptying rates are in a 1:2 ratio (Tap 1 : Tap 2). Since rate and time are inversely proportional, the time each tap takes to do the job alone is in a 2:1 ratio. This means Tap 1 is the slower tap and takes twice as long as Tap 2.

2. Combine the Power: Let the rate of the slow tap (Tap 1) be R. The rate of the fast tap (Tap 2) is 2R. When they work together, their combined rate is R + 2R = 3R.

3. Find the Time for Tap 1: The combined “power” (3R) gets the job done in 2 hours. Tap 1 only has a power of R, which is one-third of the combined power. Therefore, it will take three times as long to do the same job alone.
• Time for Tap 1 (full tank) = 3 * (Combined Time) = 3 * 2 hours = 6 hours.

4. Answer the Real Question: The question asks for the time it takes Tap 1 to empty half the tank.
• Time for half tank = (Time for full tank) / 2 = 6 hours / 2 = 3 hours.


The correct answer is (C) 3 hours.
Moderators:
Math Expert
109748 posts
Tuck School Moderator
853 posts