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David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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13 Dec 2012, 09:56
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David has d books, which is 3 times as many as Jeff and 1/2 as many as Paula. How many books do the three of them have altogether, in terms of d? (A) \(\frac{5}{6}*d\) (B) \(\frac{7}{3}*d\) (C) \(\frac{10}{3}*d\) (D) \(\frac{7}{2}*d\) (E) \(\frac{9}{2}*d\)
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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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13 Dec 2012, 09:58



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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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10 Jan 2014, 02:11
Walkabout wrote: David has d books, which is 3 times as many as Jeff and 1/2 as many as Paula. How many books do the three of them have altogether, in terms of d?
(A) 5/6*d (B) 7/3*d (C) 10/3*d (D) 7/2*d (E) 9/2*d We are given: [(d/3) = J] and [(d/2) = P], and we also have Davids own books = d Just add all three together and express them in common denominator of 3: (3/3)*d + (d/3) + (6/3)*d = (10/3)*d



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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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11 Jun 2014, 05:58
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It's also possible to solve with smart numbers David has 120 Jeff 120/3 = 40 Paula 120*2 = 240 Total 400 Books > 400/120 = 10/3
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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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12 Sep 2014, 06:30
Walkabout wrote: David has d books, which is 3 times as many as Jeff and 1/2 as many as Paula. How many books do the three of them have altogether, in terms of d?
(A) 5/6*d (B) 7/3*d (C) 10/3*d (D) 7/2*d (E) 9/2*d David = d ; jeff=f ; paula = p d=3j ; d=p(1/2) d+j+p = d+ d/3 + 2d = 10d /3



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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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30 Sep 2014, 22:11
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David ................ Jeff ................... Paula d ........................ \(\frac{d}{3}\) ....................... 2d \(Total = 3d + \frac{d}{3} = \frac{10d}{3}\) Answer = C
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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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25 May 2016, 22:21
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Attached is a visual that should help.
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Screen Shot 20160525 at 9.42.32 PM.png [ 110.22 KiB  Viewed 7366 times ]
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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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15 Jun 2016, 12:26
Walkabout wrote: David has d books, which is 3 times as many as Jeff and 1/2 as many as Paula. How many books do the three of them have altogether, in terms of d?
(A) 5/6*d (B) 7/3*d (C) 10/3*d (D) 7/2*d (E) 9/2*d Although we could plug in a real value for d, the problem can be just as easily solved by setting up equations. However, let’s start by defining some variables. Since we are given that David has d books, we can use variable d to represent how many books David has. number of books David has = d number of books Jeff has = j number of books Paula has = p We are given that David has 3 times as many books as Jeff. We can now express this in an equation. d = 3j d/3 = j We are also given that David has ½ as many books as Paula. We can also express this in an equation. d = (1/2)p 2d = p Notice that we immediately solved for j in terms of d and p in terms of d. Getting j and p in terms of d is useful when setting up our final expression. We need to determine, in terms of d, the sum of the number of books for David, Jeff, and Paula. Thus, we have: d + d/3 + 2d Getting a common denominator of 3, we have: 3d/3 + d/3 + 6d/3 = 10d/3 = 10/3*d The answer is C.
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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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15 Jul 2017, 07:59
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Hello Moderators, Do you think the answers choices should be made math friendly? It will be helpful when solving.
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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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15 Jul 2017, 09:50



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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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25 Dec 2017, 11:37
JeffTargetTestPrep wrote: Walkabout wrote: David has d books, which is 3 times as many as Jeff and 1/2 as many as Paula. How many books do the three of them have altogether, in terms of d?
(A) 5/6*d (B) 7/3*d (C) 10/3*d (D) 7/2*d (E) 9/2*d Although we could plug in a real value for d, the problem can be just as easily solved by setting up equations. However, let’s start by defining some variables. Since we are given that David has d books, we can use variable d to represent how many books David has. number of books David has = d number of books Jeff has = j number of books Paula has = p We are given that David has 3 times as many books as Jeff. We can now express this in an equation. d = 3j d/3 = j We are also given that David has ½ as many books as Paula. We can also express this in an equation. d = (1/2)p 2d = p Notice that we immediately solved for j in terms of d and p in terms of d. Getting j and p in terms of d is useful when setting up our final expression. We need to determine, in terms of d, the sum of the number of books for David, Jeff, and Paula. Thus, we have: d + d/3 + 2d Getting a common denominator of 3, we have: 3d/3 + d/3 + 6d/3 = 10d/3 = 10/3*d The answer is C. Hi. Can you please explain what does "j in terms of d and p in terms of d " mean ? I cant somehow digest the meaning of " in terms of " Thanks!



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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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25 Dec 2017, 11:42
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dave13 wrote: JeffTargetTestPrep wrote: Walkabout wrote: David has d books, which is 3 times as many as Jeff and 1/2 as many as Paula. How many books do the three of them have altogether, in terms of d?
(A) 5/6*d (B) 7/3*d (C) 10/3*d (D) 7/2*d (E) 9/2*d Although we could plug in a real value for d, the problem can be just as easily solved by setting up equations. However, let’s start by defining some variables. Since we are given that David has d books, we can use variable d to represent how many books David has. number of books David has = d number of books Jeff has = j number of books Paula has = p We are given that David has 3 times as many books as Jeff. We can now express this in an equation. d = 3j d/3 = j We are also given that David has ½ as many books as Paula. We can also express this in an equation. d = (1/2)p 2d = p Notice that we immediately solved for j in terms of d and p in terms of d. Getting j and p in terms of d is useful when setting up our final expression. We need to determine, in terms of d, the sum of the number of books for David, Jeff, and Paula. Thus, we have: d + d/3 + 2d Getting a common denominator of 3, we have: 3d/3 + d/3 + 6d/3 = 10d/3 = 10/3*d The answer is C. Hi. Can you please explain what does "j in terms of d and p in terms of d " mean ? I cant somehow digest the meaning of " in terms of " Thanks! Express x in terms of y means to write x = some equation with y. For example, in x = 12y^2  3, x is expressed in terms of y.
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Re: David has d books, which is 3 times as many as Jeff and 1/2 [#permalink]
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31 Jan 2018, 21:15
Hi All, To start, there's a typo in your transcription  it's supposed to read "...and 1/2 as many as Paula...." We can answer this question by TESTing VALUES or by doing algebra... IF... Jeff = 2 books David = 6 books = D books Paula = 12 books The total number of books = 2+6+12 = 20 So we're looking for an answer that equals 20 when D=6. There's only one answer that matches... Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: David has d books, which is 3 times as many as Jeff and 1/2
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