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A, B and C work on a task. To complete the task alone, B
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26 Jun 2014, 20:03
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A, B and C work on a task. To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone. If B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked, what proportion of the total work was completed by B? A. 1/3 B. 2/9 C. 9/49 D. 7/19 E. 1/6
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Re: A, B and C work on a task. To complete the task alone, B
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27 Jun 2014, 01:07
SravnaTestPrep wrote: A, B and C work on a task. To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone. If B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked, what proportion of the total work was completed by B?
A. 1/3 B. 2/9 C. 9/49 D. 7/19 E. 1/6 efficiency of A in doing the work = x efficiency of B in doing the work = x/2 efficiency of C in doing the work = x/3 now suppose A work for 6 days, then b will work for 3 days and C will work for 2 days proportion of work completed by B = 3(x/2) / (6x+3(x/2)+2(x/3) = 9/49



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A, B and C work on a task. To complete the task alone, B
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29 Oct 2014, 11:46
SravnaTestPrep wrote: A, B and C work on a task. To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone. If B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked, what proportion of the total work was completed by B?
A. 1/3 B. 2/9 C. 9/49 D. 7/19 E. 1/6 This is a variable question, so we can just assign arbitrary values to simplify the problem greatly. To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone. If it takes 1 day for A to do the project, then it takes 2 days for B and 3 days for C. If B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked, what proportion of the total work was completed by B? Let's say A worked 1 day. Then A completed 1 project. B worked for 1/2 a day, and since it takes him 2 days, he completed \(\frac{1/2}{2} = \frac{1}{4}\) of a project. C then worked for 1/3 of a day, and completed \(\frac{1/3}{3} = \frac{1}{9}\) of a project. Then to find the proportion, we take \(\frac{1/4}{1+1/4+1/9} = \frac{9}{49}\). Answer: C



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Re: A, B and C work on a task. To complete the task alone, B
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30 Oct 2014, 19:56
SravnaTestPrep wrote: A, B and C work on a task. To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone. If B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked, what proportion of the total work was completed by B?
A. 1/3 B. 2/9 C. 9/49 D. 7/19 E. 1/6 The first thing to notice is that A is faster than B and B is faster than C. Since work is proportional to time, in 1 day lets say if A does 2 works, B does 1 work and C does 2/3rd of a work. If A works for 2 days, B works for 1 day and C works for only 2/3 of the day. Therefore total work done = (2*2) + (1*1) + (2/3*2/3) = 49/9 Proportion of work done by B = (1*1) / (49/9) = 9/49 Hence Answer C.  Kudos please, if this post helps.



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Re: A, B and C work on a task. To complete the task alone, B
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23 Feb 2018, 19:07
Vetrik wrote: SravnaTestPrep wrote: A, B and C work on a task. To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone. If B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked, what proportion of the total work was completed by B?
A. 1/3 B. 2/9 C. 9/49 D. 7/19 E. 1/6 The first thing to notice is that A is faster than B and B is faster than C. Since work is proportional to time, in 1 day lets say if A does 2 works, B does 1 work and C does 2/3rd of a work. If A works for 2 days, B works for 1 day and C works for only 2/3 of the day. Therefore total work done = (2*2) + (1*1) + (2/3*2/3) = 49/9 Proportion of work done by B = (1*1) / (49/9) = 9/49 Hence Answer C.  Kudos please, if this post helps.How did you arrive at ...C does 2/3 of the work??? I did not understand ...B works for 3/2 times the number of days C worked???



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Re: A, B and C work on a task. To complete the task alone, B
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23 Feb 2018, 20:23
Kezia9 wrote: Vetrik wrote: SravnaTestPrep wrote: A, B and C work on a task. To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone. If B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked, what proportion of the total work was completed by B?
A. 1/3 B. 2/9 C. 9/49 D. 7/19 E. 1/6 The first thing to notice is that A is faster than B and B is faster than C. Since work is proportional to time, in 1 day lets say if A does 2 works, B does 1 work and C does 2/3rd of a work. If A works for 2 days, B works for 1 day and C works for only 2/3 of the day. Therefore total work done = (2*2) + (1*1) + (2/3*2/3) = 49/9 Proportion of work done by B = (1*1) / (49/9) = 9/49 Hence Answer C.  Kudos please, if this post helps.How did you arrive at ...C does 2/3 of the work??? I did not understand ...B works for 3/2 times the number of days C worked??? We can use ratios to understand it better Given that B worked half the number of days that A worked,implies: B= (1/2)*A Or, A/B = 2/1 (Here it means that when A works for 2 days,B works for a day). Now, relating B and C: B works 3/2 times C. Or, B= (3/2)*C B/C = 3/2. This can be rewritten as : B/C = 1/(2/3) {In other words, when B works for a day, C works for 2/3 day} Sent from my iPhone using GMAT Club Forum mobile app



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A, B and C work on a task. To complete the task alone, B
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Updated on: 05 Jul 2020, 21:45
SravnaTestPrep wrote: A, B and C work on a task. To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone. If B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked, what proportion of the total work was completed by B?
A. 1/3 B. 2/9 C. 9/49 D. 7/19 E. 1/6 Quote: To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone A=A B=2A B=\(\frac{2}{3}\)C Put the value of B here, so that we can get everything in term A so, C=3A Quote: B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked A=x B=\(\frac{1}{2}\)x B=\(\frac{3}{2}\)C In this also we put value of B so that we can get everything in term of x C=\(\frac{1}{3}\)x Now for suppose the x=6. A=6 B=3 C=2 Let,total work =1 work is done by A, \(\frac{1}{A}\)=\(\frac{W(A)}{6}\)= W(A)=\(\frac{6}{A}\) work is done by B, \(\frac{1}{2A}\)=\(\frac{W(B)}{3}\)= W(B)=\(\frac{3}{2A}\) work is done by C, \(\frac{1}{3A}\)=\(\frac{W(C)}{2}\)= W(C)=\(\frac{2}{3A}\) now the proportion of the total work was completed by B \(\frac{(32A)}{(6/A)+(3/2A)+(2/3A)}\) =\(\frac{9A}{49A}\) =9/49 IMO C
Originally posted by HouseStark on 30 Jun 2020, 00:03.
Last edited by HouseStark on 05 Jul 2020, 21:45, edited 2 times in total.



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Re: A, B and C work on a task. To complete the task alone, B
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05 Jul 2020, 09:20
HouseStark wrote: SravnaTestPrep wrote: A, B and C work on a task. To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone. If B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked, what proportion of the total work was completed by B?
A. 1/3 B. 2/9 C. 9/49 D. 7/19 E. 1/6 Quote: To complete the task alone, B takes twice the time that A would take to complete the task alone and 2/3rd the time that C would take to complete the task alone A=A B=2A B=\(\frac{2}{3}\)C Can you check and confirm: Both your assumptions are time variables: A=A is Time; A=x is also time. You have then multiplied timextime to calculate work! Am i missing something here? Put the value of B here, so that we can get everything in term A so, C=3A Quote: B actually worked for half the number of days that A worked and 3/2 times the number of days that C worked A=x B=\(\frac{1}{2}\)x B=\(\frac{3}{2}\)C In this also we put value of B so that we can get everything in term of x C=\(\frac{1}{3}\)x Now for suppose the x=6. A=6 B=3 C=2 now the proportion of the total work was completed by B \(\frac{3*3A}{6*6A+3*3A+2*2A}\) =\(\frac{9A}{49A}\) =9/49 IMO C



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Re: A, B and C work on a task. To complete the task alone, B
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05 Jul 2020, 21:49
Quote: Can you check and confirm: Both your assumptions are time variables: A=A is Time; A=x is also time. You have then multiplied timextime to calculate work! Am I missing something here? yes, I have done it wrong on the last part calculating the proportion of the total work completed by B. Thanks, Rachit4126 now, I have corrected it.




Re: A, B and C work on a task. To complete the task alone, B
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