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M and N working together, can finish a job in 6 days

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EgmatQuantExpert
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M and N working together, can finish a job in 6 days [#permalink] M and N working together, can finish a job in 6 days   Updated on: 07 May 2024, 10:20
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E

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15% (low)

Question Stats:

84% (02:13) correct 16% (02:36) wrong based on 243 sessions
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M and N working together, can finish a job in 6 days. With the help of P, they completed the job in 4 days. If Q joined them, all 4 together would have completed the job in 3\(\frac{1}{3}\) days. If all work at their respective constant rate, then in how many days Q alone can complete the work?

A. 10
B. 12
C. 15
D. 18
E. 20


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E

Originally posted by EgmatQuantExpert on 27 Aug 2018, 02:51.
Last edited by Bunuel on 07 May 2024, 10:20, edited 2 times in total.
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chetan2u
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Re: M and N working together, can finish a job in 6 days [#permalink] M and N working together, can finish a job in 6 days   27 Aug 2018, 02:59
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EgmatQuantExpert wrote:
M and N working together, can finish a job in 6 days. With the help of P, they completed the job in 4 days. If Q joined them, all 4 together would have completed the job in 31/3 days. If all work at their respective constant rate, then in how many days Q alone can complete the work?

    A. 10
    B. 12
    C. 15
    D. 18
    E. 20

To read all our articles: Must read articles to reach Q51



All four can complete the job in 3 and 1/3 days or 10/3 , so 1 day work =3/10
All except Q can complete job in 4 days, so their 1 day work=1/4

So 1 day work of Q = 3/10-1/4=(12-10)/40=1/20
So total work in 20 days..

E


EgmatQuantExpert, how can 3 people finish faster in 4 days as compared to a situation when a fourth person joins them and now in 31/3=10 days ?????
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Re: M and N working together, can finish a job in 6 days [#permalink] M and N working together, can finish a job in 6 days   27 Aug 2018, 03:13
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chetan2u wrote:

All four can complete the job in 31/3 days , so 1 day work =3/31
All except Q can complete job in 4 days, so their 1 day work=1/4

EgmatQuantExpert, how can 3 people finish faster in 4 days as compared to a situation when a fourth person joins them and now in 31/3=10 days ?????


It was a tagging error. It should be 3\(\frac{1}{3}\) days not 31/3.
We have corrected it.
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Re: M and N working together, can finish a job in 6 days [#permalink] M and N working together, can finish a job in 6 days   27 Aug 2018, 07:12
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chetan2u wrote:
EgmatQuantExpert wrote:
M and N working together, can finish a job in 6 days. With the help of P, they completed the job in 4 days. If Q joined them, all 4 together would have completed the job in 31/3 days. If all work at their respective constant rate, then in how many days Q alone can complete the work?

    A. 10
    B. 12
    C. 15
    D. 18
    E. 20

To read all our articles: Must read articles to reach Q51



All four can complete the job in 3 and 1/3 days or 10/3 , so 1 day work =3/10All except Q can complete job in 4 days, so their 1 day work=1/4

So 1 day work of Q = 3/10-1/4=(12-10)/40=1/20
So total work in 20 days..

E


EgmatQuantExpert, how can 3 people finish faster in 4 days as compared to a situation when a fourth person joins them and now in 31/3=10 days ?????


what is the reason you switched 10/3 to 3/10 ?
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Re: M and N working together, can finish a job in 6 days [#permalink] M and N working together, can finish a job in 6 days   27 Aug 2018, 07:23
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dave13 wrote:
chetan2u wrote:
EgmatQuantExpert wrote:
M and N working together, can finish a job in 6 days. With the help of P, they completed the job in 4 days. If Q joined them, all 4 together would have completed the job in 31/3 days. If all work at their respective constant rate, then in how many days Q alone can complete the work?

    A. 10
    B. 12
    C. 15
    D. 18
    E. 20

To read all our articles: Must read articles to reach Q51



All four can complete the job in 3 and 1/3 days or 10/3 , so 1 day work =3/10All except Q can complete job in 4 days, so their 1 day work=1/4

So 1 day work of Q = 3/10-1/4=(12-10)/40=1/20
So total work in 20 days..

E


EgmatQuantExpert, how can 3 people finish faster in 4 days as compared to a situation when a fourth person joins them and now in 31/3=10 days ?????


what is the reason you switched 10/3 to 3/10 ?


dave13
If someone can do a job in 10 days so each day he does 1/10 th of work..
So here also they complete the work in 10/3 days, thus in one day they can do 3/10th of work as 1/(10/3)=1*3/10=3/10

If A is doing 1/2 of the work in one day, A will complete full work in 2 days as 1/(1/2)=1*2/1=2
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Re: M and N working together, can finish a job in 6 days [#permalink] M and N working together, can finish a job in 6 days   07 May 2024, 10:18
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Re: M and N working together, can finish a job in 6 days [#permalink]
07 May 2024, 10:18
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