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It takes 6 days for 3 women and 2 men working together to
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It takes 6 days for 3 women and 2 men working together to complete a work. 3 men would do the same work 5 days sooner than 9 women. How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times
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Originally posted by virtualanimosity on 19 Aug 2009, 12:33.
Last edited by Bunuel on 04 Jul 2013, 07:11, edited 2 times in total.
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Re: Time n Work Problem
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19 Jul 2010, 09:44
nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D.
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Re: Time n Work Problem
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19 Aug 2009, 15:00
virtualanimosity wrote: It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? 1] 3 times 2] 4 times 3] 5 times 4] 6 times 5] 7 times Clear D: x: days 9 women doing the job > 1 woman works W=1/9x per day x5: days 3 men doing the job > 1 man works M=1/[3*(x5)] per day The answer to the question is: M/W And, how much is x? As per first data: 2*M+3*W=1/6 You can solve x, and obtain 2 values, 10 and 1 (1 is impossible because that would imply that the 3 men take 4 days), so x=10. So M/W=6 times
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Re: Time n Work Problem
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19 Jul 2010, 00:10
Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test?



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Re: Time n Work Problem
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19 Jul 2010, 12:05
Bunuel wrote: nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D. Hm, i got stuck cuz I got something a little different: YOURS: 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). MINE: 3 men would do the same work 5 days sooner than 9 women > \(\frac{3}{m}=\frac{9}{w}+5\) In the above equation you also have for 2 men: \(\frac{2}{m}\)  so why do u suddenly use the reciprocal? And why don't we add the 5 to women, because they take longer, hence their side is smaller...



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19 Jul 2010, 12:25
AndreG wrote: Bunuel wrote: nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D. Hm, i got stuck cuz I got something a little different: YOURS: 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). MINE: 3 men would do the same work 5 days sooner than 9 women > \(\frac{3}{m}=\frac{9}{w}+5\) In the above equation you also have for 2 men: \(\frac{2}{m}\)  so why do u suddenly use the reciprocal? And why don't we add the 5 to women, because they take longer, hence their side is smaller... Let one woman complete the job in \(w\) days and one man in \(m\) days. First equation:It takes 6 days for 3 women and 2 men working together to complete a work: As the rate of 1 woman is \(\frac{1}{w}\) job/day, then the rate of 3 women will be \(\frac{3}{w}\) job/day. As the rate of 1 man is \(\frac{1}{m}\) job/day, then the rate of 2 men will be \(\frac{2}{m}\) job/day. Combined rate of 3 women and 2 men in one day will be: \(\frac{3}{w}+\frac{2}{m}\) job/day. As they do all the job in 6 days then in 1 day they do 1/6 of the job, which is combined rate of 3 women and 2 men > \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). Second equation:3 men would do the same work 5 days sooner than 9 women: As 1 man needs \(m\) days to do the job 3 men will need \(\frac{m}{3}\) days to do the job. As 1 woman needs \(w\) days to do the job 9 women will need \(\frac{w}{9}\) days to do the job. 3 men would do the same work 5 days sooner means that 3 men will need 5 less days to do the job, hence \(\frac{m}{3}\) is 5 less than \(\frac{w}{9}\) > \(\frac{m}{3}+5=\frac{w}{9}\). Hope it's clear.
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24 Jan 2011, 09:20
First set : 3/w+2/m=1/6 Second set: 3/m = 1/x and 9/w=1/(x+5) ==> 1/m = 1/3x and 1/w = 1/9(x+5) Enter in first equation and solve for x 1/(3x+15) + 2/3x = 1/6 simplify => x^2x20=0 solve for x : x=(1 + (1+80)^,5)/2= (1+ 9)/2. X can only be positive ==> x= 5 enter in 2nd set ==> 3/m=1/5 and 9/w=1/10 => 3/2m=9/w => m/w=1/6



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06 Mar 2011, 09:42
virtualanimosity wrote: It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? 1] 3 times 2] 4 times 3] 5 times 4] 6 times 5] 7 times Let women do \(w\) units of work per day and men do \(m\) units of work per day, then question asks, what is m/w Total units of work to be done = \(6*(3*w+2*m)\) Time taken by 9 women to do this work on their own = \(6*(3*w+2*m)\)/\((9*w)\) = \(2 + 4/3*m/w\) Time taken by 3 men to do this work on their own = \(6*(3*w+2*m)/(3*m)\) = \(6/(m/w) + 4\) Let m/w be x then we know \(2 + (4/3)*x 6/x 4 = 5\) or \((4/3)*x  6/x= 7\) Now substituting for x from choices will quickly give us x = 6 so D I like this as it reduces quickly to the required form of m/w and it obviates the need for a quadratic equation and also lest w and m remain in numerator most of the time



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Re: Time n Work Problem
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06 Mar 2011, 21:08
virtualanimosity wrote: It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? 1] 3 times 2] 4 times 3] 5 times 4] 6 times 5] 7 times I received a PM asking me to respond. First, this is definitely not a realistic GMAT question. For one thing, it's horribly written (the phrase 'to complete a work' is not English, the question should read '*By* how many times...', the question needs to make clear that each man works at the same rate, as does each woman, the word 'sooner' is nonidiomatic, the word 'output' is misused, etc). For another, it's terribly contrived, and altogether tedious if you take any normal approach; I don't see any direct way to solve that will allow you to avoid a quadratic equation. Real GMAT questions are never designed in such a way, so you can confidently move on to better material and ignore this question (incidentally, where is it from?). While it isn't especially fast either, you can work backwards from the answers here relatively easily. This might at least be less confusing for some than a direct (algebraic) approach. Say we get 1 unit of work per woman per day. If you test, say, answer C, we'd then get 5 units of work per man per day. The job would then require 6(3 + 2*5) = 78 units of work. Notice that, to find how long it will take 9 women to do the job, we'll need to get an integer when we divide 78 by 9, so C cannot be right. If you move next to D, we have 6 units of work per man per day, and the job requires 6(3 + 2*6) = 90 units of work. Thus 9 women do the job in 10 days, and 3 men would do the job in 90/(6*3) = 5 days, so D is correct.
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Re: It takes 6 days for 3 women and 2 men working together to
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15 Sep 2012, 10:53
virtualanimosity wrote: It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman?
A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times The fastest and easiest way to solve this question was already proposed by IanStewart. I am trying another algebraic approach. Denote by \(W\) the rate of a woman, by \(M\) that of a men, and by \(T\) the time it takes 9 women to complete the work. We have the following equations: \(6(3W + 2M) = 9WT = 3M(T5)\), or, after reducing by 3, \(2(3W + 2M) = 3WT = M(T  5).\) We are looking for the ratio \(M/W\) which we can denote by \(n.\) Substituting in the above equations \(M = nW,\) we can write: \(2(3W + 2nW) = 3WT = nW(T  5).\) Divide through by \(W,\) so \(6 + 4n = 3T = nT  5n.\) Solving for \(T\) (equality between the last two expressions) we obtain \(T=\frac{5n}{n3}.\) Taking the equality of the first two expressions, we get \(6+4n=\frac{3\cdot{5}n}{n3}.\) From the possible answer choices we can deduce that \(n\) must be a positive integer. We need \(\frac{15n}{n3}\) to be a positive integer. We can see that \(n\) cannot be odd and it must be greater than 3. We have to choose between B and D. Only \(n = 6\) works. Answer D.
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19 Sep 2012, 14:56
Bunuel wrote: nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D. How did you solve for m and w in the very last part? I do the algebra and can't get the right answer. You have one equation with 2 unknown variables.



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19 Sep 2012, 22:39
Shawshank wrote: Bunuel wrote: nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D. How did you solve for m and w in the very last part? I do the algebra and can't get the right answer. You have one equation with 2 unknown variables. You have 2 equations with two unknowns: First equation \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}.\) Second equation \(\frac{m}{3}+5=\frac{w}{9}\). After getting rid of the denominators (multiply first equation by \(6wm\) and the second by 9), for example express \(w\) from the second equation and substitute it into the first. You obtain a quadratic equation for \(m\): \(m^23m180=0\) This equation has one positive and one negative root. The sum of the two roots must be 3 and their product 180. Using factorization for 180, you can find 12 and 15. So \(m=15\) and \(w=90.\) For another algebraic approach see: ittakes6daysfor3womenand2menworkingtogetherto82718.html#p1121807
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Re: Time n Work Problem
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30 Sep 2013, 00:44
Bunuel wrote: nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D. Can you please help me to understand on what logic did you make this explanation 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\).
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30 Sep 2013, 01:07
honchos wrote: Bunuel wrote: nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D. Can you please help me to understand on what logic did you make this explanation 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\).One man completes the job in \(m\) days > 3 men in m/3 days. One woman completes the job in \(w\) days > 9 women in w/9 days. We are told that m/3 is 5 less than w/9 > \(\frac{m}{3}+5=\frac{w}{9}\). Hope it's clear.
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Re: Time n Work Problem
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20 Nov 2013, 10:58
Bunuel wrote: AndreG wrote: Bunuel wrote: Below is another solution which is a little bit faster.
It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times
Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day.
It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\).
3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\).
Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\).
Answer: D.
Hm, i got stuck cuz I got something a little different: YOURS: 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). MINE: 3 men would do the same work 5 days sooner than 9 women > \(\frac{3}{m}=\frac{9}{w}+5\) In the above equation you also have for 2 men: \(\frac{2}{m}\)  so why do u suddenly use the reciprocal? And why don't we add the 5 to women, because they take longer, hence their side is smaller... Let one woman complete the job in \(w\) days and one man in \(m\) days. First equation:It takes 6 days for 3 women and 2 men working together to complete a work: As the rate of 1 woman is \(\frac{1}{w}\) job/day, then the rate of 3 women will be \(\frac{3}{w}\) job/day. As the rate of 1 man is \(\frac{1}{m}\) job/day, then the rate of 2 men will be \(\frac{2}{m}\) job/day. Combined rate of 3 women and 2 men in one day will be: \(\frac{3}{w}+\frac{2}{m}\) job/day. As they do all the job in 6 days then in 1 day they do 1/6 of the job, which is combined rate of 3 women and 2 men > \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). Second equation:3 men would do the same work 5 days sooner than 9 women: As 1 man needs \(m\) days to do the job 3 men will need \(\frac{m}{3}\) days to do the job. As 1 woman needs \(w\) days to do the job 9 women will need \(\frac{w}{9}\) days to do the job. 3 men would do the same work 5 days sooner means that 3 men will need 5 less days to do the job, hence \(\frac{m}{3}\) is 5 less than \(\frac{w}{9}\) > \(\frac{m}{3}+5=\frac{w}{9}\). Hope it's clear. My question is this, on the second equation how did you KNOW to put m/3, whereas in the first it was 2/m? In both cases aren't you figuring out the rate? In the first equation, you know that a man does 1/m of the job, and that 2 would do 2/m. In the second equation the rate is still 1/m, but you have 3 men, so should it not be 3/m+5=9/m?



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21 Nov 2013, 01:48
AccipiterQ wrote: Bunuel wrote: AndreG wrote: Hm, i got stuck cuz I got something a little different: YOURS: 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\).
MINE: 3 men would do the same work 5 days sooner than 9 women > \(\frac{3}{m}=\frac{9}{w}+5\)
In the above equation you also have for 2 men: \(\frac{2}{m}\)  so why do u suddenly use the reciprocal? And why don't we add the 5 to women, because they take longer, hence their side is smaller... Let one woman complete the job in \(w\) days and one man in \(m\) days. First equation:It takes 6 days for 3 women and 2 men working together to complete a work: As the rate of 1 woman is \(\frac{1}{w}\) job/day, then the rate of 3 women will be \(\frac{3}{w}\) job/day. As the rate of 1 man is \(\frac{1}{m}\) job/day, then the rate of 2 men will be \(\frac{2}{m}\) job/day. Combined rate of 3 women and 2 men in one day will be: \(\frac{3}{w}+\frac{2}{m}\) job/day. As they do all the job in 6 days then in 1 day they do 1/6 of the job, which is combined rate of 3 women and 2 men > \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). Second equation:3 men would do the same work 5 days sooner than 9 women: As 1 man needs \(m\) days to do the job 3 men will need \(\frac{m}{3}\) days to do the job. As 1 woman needs \(w\) days to do the job 9 women will need \(\frac{w}{9}\) days to do the job. 3 men would do the same work 5 days sooner means that 3 men will need 5 less days to do the job, hence \(\frac{m}{3}\) is 5 less than \(\frac{w}{9}\) > \(\frac{m}{3}+5=\frac{w}{9}\). Hope it's clear. My question is this, on the second equation how did you KNOW to put m/3, whereas in the first it was 2/m? In both cases aren't you figuring out the rate? In the first equation, you know that a man does 1/m of the job, and that 2 would do 2/m. In the second equation the rate is still 1/m, but you have 3 men, so should it not be 3/m+5=9/m? Please read the solution carefully: First equation gives the rate: the rate of 1 man is \(\frac{1}{m}\) job/day, then the rate of 2 men will be \(\frac{2}{m}\) job/day. Second equation gives time: 1 man needs \(m\) days to do the job 3 men will need \(\frac{m}{3}\) days to do the job. Hope it's clear.
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Re: Time n Work Problem
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17 Jan 2014, 22:26
Bunuel wrote: nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D. bunuel, pls help if i equate time i am not getting it pls tell me where i am going wrong lets take 1 woman can complete the work in 'w' days and 1 man can complete in 'm' days so, it becomes w/3+m/2=6 and m/3+5=w/9 but i am getting the answer wrong. thanks in advance



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Re: Time n Work Problem
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18 Jan 2014, 02:22
saggii27 wrote: Bunuel wrote: nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D. bunuel, pls help if i equate time i am not getting it pls tell me where i am going wrong lets take 1 woman can complete the work in 'w' days and 1 man can complete in 'm' days so, it becomes w/3+m/2=6 and m/3+5=w/9 but i am getting the answer wrong. thanks in advance That's because your equations are wrong. If one woman complete the job in \(w\) days and one man in \(m\) days, then w/3 is the time one woman needs to complete 1/3 of the work and m/2 is the time one man needs to complete 1/2 of the work. Adding them makes no sense. We can add rates but not times. Check here: ittakes6daysfor3womenand2menworkingtogetherto82718.html#p751436Hope this helps.
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Re: Time n Work Problem
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06 Feb 2014, 09:16
Bunuel wrote: nonameee wrote: Guys, even if you know the solution right away, it takes several minutes (definitely more than 3) to just write it down to find the answer. Is it a real GMAT question? Can something like that be expected on the real test? Below is another solution which is a little bit faster. It takes 6 days for 3 women and 2 men working together to complete a work.3 men would do the same work 5 days sooner than 9 women.How many times does the output of a man exceed that of a woman? A. 3 times B. 4 times C. 5 times D. 6 times E. 7 times Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. It takes 6 days for 3 women and 2 men working together to complete a work > sum the rates: \(\frac{3}{w}+\frac{2}{m}=\frac{1}{6}\). 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). Solving: \(m=15\) and \(w=90\). \(\frac{w}{m}=6\). Answer: D. I stumbled on this answer and think it's worth clarifying: In the second equation: 3 men would do the same work 5 days sooner than 9 women > \(\frac{m}{3}+5=\frac{w}{9}\). m and w are representing TOTAL work done by men and women. Whereas in the first equation: Let one woman complete the job in \(w\) days and one man in \(m\) days. So the rate of 1 woman is \(\frac{1}{w}\) job/day and the rate of 1 man is \(\frac{1}{m}\) job/day. m and w are representing the RATE of work done by men and women. I hope this is correct (Bunuel can you confirm?) and has helped some grasp the concept.




Re: Time n Work Problem &nbs
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