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

It is currently 16 Oct 2019, 05:07

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

Working independently, Tina can do a certain job in 12 hours

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

Hide Tags

Find Similar Topics 
Retired Moderator
avatar
V
Joined: 22 Jun 2014
Posts: 1093
Location: India
Concentration: General Management, Technology
GMAT 1: 540 Q45 V20
GPA: 2.49
WE: Information Technology (Computer Software)
GMAT ToolKit User
Working independently, Tina can do a certain job in 12 hours  [#permalink]

Show Tags

New post 27 Nov 2018, 09:06
3
1
1
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

89% (01:27) correct 11% (02:03) wrong based on 145 sessions

HideShow timer Statistics

Working independently, Tina can do a certain job in 12 hours. Working independently, Ann can do the same job in 9 hours. If Tina works independently at the job for 8 hours and then Ann works independently, how many hours will it take Ann to complete the remainder of the job?

(A) 2/3
(B) 3/4
(C) 1
(D) 2
(E) 3

Project PS Butler : Question #43


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS

_________________
VP
VP
User avatar
D
Joined: 09 Mar 2016
Posts: 1230
Re: Working independently, Tina can do a certain job in 12 hours  [#permalink]

Show Tags

New post 27 Nov 2018, 11:05
1
2
HKD1710 wrote:
Working independently, Tina can do a certain job in 12 hours. Working independently, Ann can do the same job in 9 hours. If Tina works independently at the job for 8 hours and then Ann works independently, how many hours will it take Ann to complete the remainder of the job?

(A) 2/3
(B) 3/4
(C) 1
(D) 2
(E) 3

Project PS Butler : Question #43


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS



Work done by Tina \(\frac{8}{12}\)

Work left to be done \(\frac{1}{3}\)

Ann`s Rate \(\frac{1}{9}\)

To find how much time it will take for Ann to complete remainder of job divide work by rate

i.e \(\frac{\frac{1}{3}}{\frac{1}{9}}\) = \(\frac{1}{3} *\frac{9}{1}\) = \(3\)

IMO: E :)
Director
Director
avatar
G
Joined: 09 Mar 2018
Posts: 996
Location: India
Re: Working independently, Tina can do a certain job in 12 hours  [#permalink]

Show Tags

New post 10 Feb 2019, 00:54
HKD1710 wrote:
Working independently, Tina can do a certain job in 12 hours. Working independently, Ann can do the same job in 9 hours. If Tina works independently at the job for 8 hours and then Ann works independently, how many hours will it take Ann to complete the remainder of the job?

(A) 2/3
(B) 3/4
(C) 1
(D) 2
(E) 3


Rate of R = W/12 = 3 units/hr
Rate of A = W/9 = 4 units/hr

Let W = 36 units

R works for 8 hrs means work done = 24 units

Remaining work = 12 units

A works for 3 hrs for the remaining 12 units
_________________
If you notice any discrepancy in my reasoning, please let me know. Lets improve together.

Quote which i can relate to.
Many of life's failures happen with people who do not realize how close they were to success when they gave up.
e-GMAT Representative
User avatar
V
Joined: 04 Jan 2015
Posts: 3074
Working independently, Tina can do a certain job in 12 hours  [#permalink]

Show Tags

New post Updated on: 13 Feb 2019, 22:28

Solution


Given:
    • Working independently, Tina can do a certain job in 12 hours.
    • Working independently, Ann can do the same job in 9 hours.
    • Tina works independently at the job for 8 hours and then Ann works independently.

To find:
    • The time taken by Ann, to complete the remainder of the job.

Approach and Working:
Let us assume the total job = LCM (12, 9) = 36 units

    • 1-hour job of Tina = \(\frac{36}{12}\) = 3 units
    • 1-hour job of Ann = \(\frac{36}{9}\) = 4 units

As Tina works for the first 8 hours, the amount of work done by Tina = 3 x 8 = 24 units

Hence, remaining job = 36 – 24 = 12 units
Therefore, the time taken by Ann = \(\frac{12}{4}\) = 3 hours

Hence, the correct answer is option E.

Answer: E

Image

_________________

Originally posted by EgmatQuantExpert on 10 Feb 2019, 05:35.
Last edited by EgmatQuantExpert on 13 Feb 2019, 22:28, edited 1 time in total.
GMAT Club Legend
GMAT Club Legend
User avatar
D
Joined: 18 Aug 2017
Posts: 5005
Location: India
Concentration: Sustainability, Marketing
GPA: 4
WE: Marketing (Energy and Utilities)
GMAT ToolKit User Premium Member
Re: Working independently, Tina can do a certain job in 12 hours  [#permalink]

Show Tags

New post 10 Feb 2019, 05:40
HKD1710 wrote:
Working independently, Tina can do a certain job in 12 hours. Working independently, Ann can do the same job in 9 hours. If Tina works independently at the job for 8 hours and then Ann works independently, how many hours will it take Ann to complete the remainder of the job?

(A) 2/3
(B) 3/4
(C) 1
(D) 2
(E) 3

Project PS Butler : Question #43


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS


rate of Tina = 1/12
Rate of Ann = 1/9

so work done by tina n 8 hrs
x/12 * 8 = 2x/3
left = x/3
so Ann would take
x/3 * 9 = 3 hrs
x = 1
IMO E
GMAT Club Bot
Re: Working independently, Tina can do a certain job in 12 hours   [#permalink] 10 Feb 2019, 05:40
Display posts from previous: Sort by

Working independently, Tina can do a certain job in 12 hours

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





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