GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 24 Mar 2019, 04:11

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

In a certain task, a person has to fill an empty tank using four taps

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

 
e-GMAT Representative
User avatar
D
Joined: 04 Jan 2015
Posts: 2722
In a certain task, a person has to fill an empty tank using four taps  [#permalink]

Show Tags

New post 13 Feb 2019, 06:15
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

57% (01:46) correct 43% (02:22) wrong based on 51 sessions

HideShow timer Statistics

In a certain task, a person has to fill an empty tank using four taps, each of which can fill the entire empty tank in 1 hour, and once the tank is filled completely, he needs to empty the tank using two outlets, at the bottom of the tank. Both the outlets can empty the full tank in same time. How much time does an outlet take to empty a full tank, if the total time taken by the person to finish the task is 30 minutes?

    A. 1/4 hour
    B. 1/3 hour
    C. 1/2 hour
    D. 3/4 hour
    E. 1 hour


To read all our articles: Must Read Articles and Practice Questions to score Q51

Image

_________________








Register for free sessions
Number Properties:- Get 5 free video lessons, 50 practice questions | Algebra:-Get 4 free video lessons, 40 practice questions
Quant Workshop:- Get 100 practice questions | Free Strategy Session:- Key strategy to score 760

Success Stories
Q38 to Q50- Interview call form Wharton | Q35 to Q50 | More Success Stories

Ace GMAT
Articles and Questions to reach Q51 | Question of the week | Tips From V40+ Scorers | V27 to V42:- GMAT 770 | Guide to Get into ISB-MBA

Must Read Articles
Number Properties – Even Odd | LCM GCD | Statistics-1 | Statistics-2 | Remainders-1 | Remainders-2
Word Problems – Percentage 1 | Percentage 2 | Time and Work 1 | Time and Work 2 | Time, Speed and Distance 1 | Time, Speed and Distance 2
Advanced Topics- Permutation and Combination 1 | Permutation and Combination 2 | Permutation and Combination 3 | Probability
Geometry- Triangles 1 | Triangles 2 | Triangles 3 | Common Mistakes in Geometry
Algebra- Wavy line | Inequalities

Practice Questions
Number Properties 1 | Number Properties 2 | Algebra 1 | Geometry | Prime Numbers | Absolute value equations | Sets



| '4 out of Top 5' Instructors on gmatclub | 70 point improvement guarantee | www.e-gmat.com

Manager
Manager
avatar
B
Joined: 18 Oct 2018
Posts: 68
Location: India
Concentration: Finance, International Business
GPA: 4
WE: Business Development (Retail Banking)
CAT Tests
Re: In a certain task, a person has to fill an empty tank using four taps  [#permalink]

Show Tags

New post 13 Feb 2019, 06:22
Time taken by 1 tap to fill tank= 1 hour.
So,time taken to fill the tank when all 4 taps are open= 1/4 hours= 15 minutes.

Since total time taken by the person=30 minutes,
This means that the tank is emptied in 30-15 minutes= 15 minutes.

Now,since 2 taps have equal work rate to empty the tank,this means that the 2 taps took 15 minutes,
Thus,one tap took 30 minutes to empty the tank= 1/2 hours.

Hence,C

Posted from my mobile device
Manager
Manager
User avatar
G
Joined: 13 Jan 2018
Posts: 245
Location: India
Concentration: Operations, General Management
GMAT 1: 580 Q47 V23
GMAT 2: 640 Q49 V27
GPA: 4
WE: Consulting (Consulting)
Reviews Badge
Re: In a certain task, a person has to fill an empty tank using four taps  [#permalink]

Show Tags

New post 13 Feb 2019, 22:14
1
1 tap can fill a tank in 1 hour, then 4 taps can fille the tank in \(\frac{1}{4}\) hour

i.e, 4 taps fill the tank in 15 minutes. Now the entire task of filling the tank and emptying the tank is completed in 30 minutes. So in 30 minutes, the first 15 minutes were to fill the tank and the rest 15 minutes were to empty the tank.

So 2 taps took 15 minutes to empty the tank, then each tap takes 30 minutes to empty the tank.

30 minutes = \(\frac{1}{2}\) hour

OPTION: C
_________________

____________________________
Regards,

Chaitanya


+1 Kudos

if you like my explanation!!!

Intern
Intern
avatar
B
Joined: 12 Feb 2019
Posts: 1
Location: India
GMAT ToolKit User
Re: In a certain task, a person has to fill an empty tank using four taps  [#permalink]

Show Tags

New post 13 Feb 2019, 22:26
Option: C
time taken for filling => 60 mins/4 = 15 mins (since all taps fill at equal rate)
Total activity time (time to fill + time to empty tank) = 30 mins
therefore, Time taken to empty tank by 2 outlets = 30 - 15 = 15 mins
Since outlets empty at equal rate, time needed by each outlet to empty tank = 15x2 = 30 mins
e-GMAT Representative
User avatar
D
Joined: 04 Jan 2015
Posts: 2722
Re: In a certain task, a person has to fill an empty tank using four taps  [#permalink]

Show Tags

New post 14 Feb 2019, 22:40

Solution



Given:
In this question, we are given
    • In a certain task, a person has to fill an empty tank using four taps, each of which can fill the entire empty tank in 1 hour.
    • Once the tank is filled completely, he needs to empty the tank using two outlets, at the bottom of the tank.
    • Both the outlets can empty the full tank in same time.
    • The total time taken by the person to finish the task is 30 minutes.

To find:
We need to determine
    • The amount of time does an outlet tap take to empty a full tank.

Approach and Working:
As each inlet tap can fill the tank in 1 hour, while 4 taps are working together, the tap will be filled in \(\frac{1}{4}\) hour = 15 minutes
    • Hence, in (30 – 15) = 15 minutes the two outlet taps can empty the tank.
    • As both outlet taps can empty the tank at the same time, each of them individually can empty the tank in 15 x 2 = 30 minutes or \(\frac{1}{2}\) hour.

Hence the correct answer is Option C.

Answer: C


Image

_________________








Register for free sessions
Number Properties:- Get 5 free video lessons, 50 practice questions | Algebra:-Get 4 free video lessons, 40 practice questions
Quant Workshop:- Get 100 practice questions | Free Strategy Session:- Key strategy to score 760

Success Stories
Q38 to Q50- Interview call form Wharton | Q35 to Q50 | More Success Stories

Ace GMAT
Articles and Questions to reach Q51 | Question of the week | Tips From V40+ Scorers | V27 to V42:- GMAT 770 | Guide to Get into ISB-MBA

Must Read Articles
Number Properties – Even Odd | LCM GCD | Statistics-1 | Statistics-2 | Remainders-1 | Remainders-2
Word Problems – Percentage 1 | Percentage 2 | Time and Work 1 | Time and Work 2 | Time, Speed and Distance 1 | Time, Speed and Distance 2
Advanced Topics- Permutation and Combination 1 | Permutation and Combination 2 | Permutation and Combination 3 | Probability
Geometry- Triangles 1 | Triangles 2 | Triangles 3 | Common Mistakes in Geometry
Algebra- Wavy line | Inequalities

Practice Questions
Number Properties 1 | Number Properties 2 | Algebra 1 | Geometry | Prime Numbers | Absolute value equations | Sets



| '4 out of Top 5' Instructors on gmatclub | 70 point improvement guarantee | www.e-gmat.com

GMAT Club Bot
Re: In a certain task, a person has to fill an empty tank using four taps   [#permalink] 14 Feb 2019, 22:40
Display posts from previous: Sort by

In a certain task, a person has to fill an empty tank using four taps

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.