Author 
Message 
Founder
Joined: 04 Dec 2002
Posts: 15147
Location: United States (WA)

GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
07 Jun 2009, 01:13
GMAT Diagnostic Test Question 45Field: algebra Difficulty: 750
5 boxes are placed in a stack by weight from lightest to heaviest. If the heaviest box weighs \(x\) kg, then the next heaviest weighs \(x%\) less than the heaviest box. If this secondheaviest box weighs \(y\) kg, then the next heaviest weighs \(y%\) less than this secondheaviest box. And so on, for all 5 boxes. If the heaviest box weighs 10kg, approximately what percent less weight is the lightest box than the heaviest one? A. 30 B. 40 C. 50 D. 60 E. 70 THIS QUESTION WAS REMOVED FROM THE TESTS
_________________
Founder of GMAT Club
US News Rankings progression  last 10 years in a snapshot  New! Just starting out with GMAT? Start here... Need GMAT Book Recommendations? Best GMAT Books
Coauthor of the GMAT Club tests
Last edited by Bunuel on 16 Jun 2013, 22:30, edited 4 times in total.
Clarified the setup



Intern
Joined: 30 Apr 2010
Posts: 25

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
30 Apr 2010, 14:03
3
This post received KUDOS
This is a badlyworded question. bb wrote: GMAT Diagnostic Test Question 45
5 boxes are placed in a stack by weight from lightest to heaviest. The heaviest box weighs \(x\) kg and then next heaviest weighs \(x%\) less than the heaviest box and the next heaviest box weighs \(xx%\) less than the next heaviest, and so on. If the heaviest box weighs 10kg, approximately what percent less weight is the lightest box than the heaviest one?
A. 30 B. 40 C. 50 D. 60 E. 70 "The heaviest box weighs \(x\) kg and then next heaviest weighs \(x%\) less than the heaviest box" Except for the "then" typo, so far so good. "the next heaviest box weighs \(xx%\) less than the next heaviest" If I follow the OE, this is not written correctly. First, it shouldn't say "than the next heaviest"; it should say "than the previous heaviest box". Second, \(xx%\) makes no sense. The OE says "The weight of the second heaviest box = x – x% of x = 10 kg – 10% of 10 kg = 9 kg". In other words, the secondheaviest box should weigh \(x  x * x%\). So the thirdheaviest box should weigh \((x  x * x%)%\) less than \(x  x * x%\). Not only is this wrong, but it's way too complicated and the wording forces you to give part of the answer away. I would simply write: If the heaviest box weighs \(x\) kg, then the next heaviest weighs \(x%\) less than the heaviest box. If this secondheaviest box weighs \(y\) kg, then the next heaviest weighs \(y%\) less than this secondheaviest box. And so on, for all 5 boxes.



Director
Joined: 29 Aug 2005
Posts: 860

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
18 Jul 2009, 13:20
2
This post received KUDOS
Seeing how it is being solved, I can tell that "same ratio" can be dubious. For example, I "solved" it as 10*0.9^4



Current Student
Joined: 13 Jul 2009
Posts: 145
Location: Barcelona
Schools: SSE

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
18 Jul 2009, 12:21
1
This post received KUDOS
The question says Quote: approximately what percent less weight is the lightest box than the heaviest one? So 10  6.95 = 3.05 less weight = 30%, wich is Answer A.
_________________
Performance: Gmat  Toefl Contributions: The Idioms Test  All Geometry Formulas  Friendly Error Log  GMAT Analytics MSc in Management: All you need to know  Student Lifestyle  Class Profiles



Manager
Joined: 14 Aug 2009
Posts: 123

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
23 Aug 2009, 10:14
1
This post received KUDOS
bb wrote: GMAT Diagnostic Test Question 45Field: algebra Difficulty: 750
5 boxes are placed in a stack by weight from lightest to heaviest. The heaviest box weighs \(x\) kg and then next heaviest weighs \(x%\) less than the heaviest box and the next heaviest box weighs \(xx%\) less than the next heaviest, and so on. If the heaviest box weighs 10kg, approximately what percent less weight is the lightest box than the heaviest one? A. 30 B. 40 C. 50 D. 60 E. 70 "weighs \(xx%\) less than the next heaviest..." it's not easy to know what this sentence mean...
_________________
Kudos me if my reply helps!



SVP
Joined: 29 Aug 2007
Posts: 2473

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
14 Jun 2009, 10:53
Explanation
Official Answer: AGiven that the weight of the heaviest box = x kg = 10 kg The weight of the second heaviest box = x – x% of x = 10 kg – 10% of 10 kg = 9 kg The weight of the third heaviest box = 9 kg – 9% of 9 kg = 8.19 kg The weight of the fourth heaviest box = 8.19 kg – 8.19 % of 8.19 kg = 7.52kg The weight of the lightest box = 7.52 kg – 7.52% of 7.52 kg = 6.95 kg The weight of the lightest box/ the weight of the heaviest box \(= 1  \frac{6.95}{10} \approx 30%\), which is A.
_________________
Verbal: http://gmatclub.com/forum/newtotheverbalforumpleasereadthisfirst77546.html Math: http://gmatclub.com/forum/newtothemathforumpleasereadthisfirst77764.html Gmat: http://gmatclub.com/forum/everythingyouneedtoprepareforthegmatrevised77983.html
GT



Founder
Joined: 04 Dec 2002
Posts: 15147
Location: United States (WA)

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
18 Jul 2009, 14:07
seofah wrote: Seeing how it is being solved, I can tell that "same ratio" can be dubious. For example, I "solved" it as 10*0.9^4 Thank you! I agree  rephrasing the question...
_________________
Founder of GMAT Club
US News Rankings progression  last 10 years in a snapshot  New! Just starting out with GMAT? Start here... Need GMAT Book Recommendations? Best GMAT Books
Coauthor of the GMAT Club tests



Founder
Joined: 04 Dec 2002
Posts: 15147
Location: United States (WA)

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
18 Jul 2009, 14:08
saruba wrote: The question says Quote: approximately what percent less weight is the lightest box than the heaviest one? So 10  6.95 = 3.05 less weight = 30%, wich is Answer A. GMAT Tiger will answer this one.
_________________
Founder of GMAT Club
US News Rankings progression  last 10 years in a snapshot  New! Just starting out with GMAT? Start here... Need GMAT Book Recommendations? Best GMAT Books
Coauthor of the GMAT Club tests



SVP
Joined: 29 Aug 2007
Posts: 2473

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
18 Jul 2009, 22:02
Agreed and modified the OA accordingly. Thanks for the suggestion. GT GMAT TIGER wrote: Explanation
Official Answer: AGiven that the weight of the heaviest box = x kg = 10 kg The weight of the second heaviest box = x – x% of x = 10 kg – 10% of 10 kg = 9 kg The weight of the third heaviest box = 9 kg – 9% of 9 kg = 8.19 kg The weight of the fourth heaviest box = 8.19 kg – 8.19 % of 8.19 kg = 7.52kg The weight of the lightest box = 7.52 kg – 7.52% of 7.52 kg = 6.95 kg The weight of the lightest box/ the weight of the heaviest box \(= 1  \frac{6.95}{10} \approx 30%\), which is A.
_________________
Verbal: http://gmatclub.com/forum/newtotheverbalforumpleasereadthisfirst77546.html Math: http://gmatclub.com/forum/newtothemathforumpleasereadthisfirst77764.html Gmat: http://gmatclub.com/forum/everythingyouneedtoprepareforthegmatrevised77983.html
GT



Intern
Joined: 09 Apr 2008
Posts: 2

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
24 Jul 2009, 06:09
The pdf and the excel sheet mention OA as E  It should be corected



SVP
Joined: 30 Apr 2008
Posts: 1874
Location: Oklahoma City
Schools: Hard Knocks

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
14 Aug 2009, 21:05
I think this question is difficult from a time consuming stand point. Once a person understands what they need to do, the person just has to crunch the numbers and get close to 3 kgs less so they know A is the correct answer. I'm thinking this is about a 650700 question. If you really wanted to make it a 750 question (in my opinion) make it a symbolism question. I know a lot of people that are in the upper 600s that want to break through to the low 700s and into mid700s have a very difficult time with symbolism.
_________________
 J Allen Morris **I'm pretty sure I'm right, but then again, I'm just a guy with his head up his a$$.
GMAT Club Premium Membership  big benefits and savings



Founder
Joined: 04 Dec 2002
Posts: 15147
Location: United States (WA)

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
14 Aug 2009, 23:46
jallenmorris wrote: I think this question is difficult from a time consuming stand point. Once a person understands what they need to do, the person just has to crunch the numbers and get close to 3 kgs less so they know A is the correct answer. I'm thinking this is about a 650700 question. If you really wanted to make it a 750 question (in my opinion) make it a symbolism question.
I know a lot of people that are in the upper 600s that want to break through to the low 700s and into mid700s have a very difficult time with symbolism. Thanks! By symbolism you mean "@"?
_________________
Founder of GMAT Club
US News Rankings progression  last 10 years in a snapshot  New! Just starting out with GMAT? Start here... Need GMAT Book Recommendations? Best GMAT Books
Coauthor of the GMAT Club tests



SVP
Joined: 30 Apr 2008
Posts: 1874
Location: Oklahoma City
Schools: Hard Knocks

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
15 Aug 2009, 08:27
@ would work. Anything actually. The more abstract the better. I think @ is used often so it would be a good choice. Of course, you don't have to change the question, it was just a suggestion. bb wrote: jallenmorris wrote: I think this question is difficult from a time consuming stand point. Once a person understands what they need to do, the person just has to crunch the numbers and get close to 3 kgs less so they know A is the correct answer. I'm thinking this is about a 650700 question. If you really wanted to make it a 750 question (in my opinion) make it a symbolism question.
I know a lot of people that are in the upper 600s that want to break through to the low 700s and into mid700s have a very difficult time with symbolism. Thanks! By symbolism you mean "@"?
_________________
 J Allen Morris **I'm pretty sure I'm right, but then again, I'm just a guy with his head up his a$$.
GMAT Club Premium Membership  big benefits and savings



SVP
Joined: 29 Aug 2007
Posts: 2473

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
15 Aug 2009, 17:50
Lets make it a little polished and improved: bb wrote: 5 boxes are placed in a stack by weight from lightest to heaviest. The heaviest box weighs \(x\) kg and then next heaviest weighs \(x%\) less than the heaviest box and the next heaviest box weighs \(xx%\) less than the next heaviest, and so on. Approximately what is the weight of the lightest box?
A. .3x B. .4x C. .5x D. .6x E. .7x It is not an easy question because it, I mean the original ones as well, doesnot have any direct/quick way to get the answer. The calculation is cumbersome and time consuming. Its difficult to solve it in 2 minuets. This way it is 700+ or 750 level question. In terms of solution, it may not be a 750 level question.
_________________
Verbal: http://gmatclub.com/forum/newtotheverbalforumpleasereadthisfirst77546.html Math: http://gmatclub.com/forum/newtothemathforumpleasereadthisfirst77764.html Gmat: http://gmatclub.com/forum/everythingyouneedtoprepareforthegmatrevised77983.html
GT



Director
Joined: 01 Apr 2008
Posts: 881
Name: Ronak Amin
Schools: IIM Lucknow (IPMX)  Class of 2014

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
17 Aug 2009, 13:59
The question was a bit confusing for me: The heaviest box weighs x kg and then next heaviest weighs x% less than the heaviest box and the next heaviest box weighs xx% less than the next heaviest, and so on.
The heaviest box( top box ) weighs x kg and then next heaviest (top1 box )weighs x% less than the heaviest box (top box) and the next heaviest box ( top1/top2? box ) weighs xx% less than the next heaviest (top1 ? ), and so on.



Intern
Joined: 03 Jun 2009
Posts: 1

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
23 Aug 2009, 02:23
bb wrote: 5 boxes are placed in a stack by weight from lightest to heaviest. The heaviest box weighs \(x\) kg and then next heaviest weighs \(x%\) less than the heaviest box and the next heaviest box weighs \(xx%\) less than the next heaviest, and so on. If the heaviest box weighs 10kg, approximately what percent less weight is the lightest box than the heaviest one?
I think the question is a little bid confusingly made. It says that the heaviest box weighs x kg and that the value of this box is 10 kg, which means that x is 10. Thus we subtract 10%. But then x equals 9% then 8,19... guess somewhere should be indicated that the x% equals the values of the boxes, not exactly 10 but each box and x is not stable but changes every time we move to the next box. Let me know your thoughts



Manager
Joined: 27 Oct 2009
Posts: 143
Location: Montreal
Schools: Harvard, Yale, HEC

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
29 Oct 2009, 06:40
I think this question should not be on the real GMAT exam since the question itself is too confusing. I bet 90% of the people in this forum did find the expression xx% confusing. Even someone know the concept and know what to do, it is still impossible to try to do all these calculation under 2 min without a calculator. Maybe there is another solution???



Manager
Joined: 22 Sep 2009
Posts: 215
Location: Tokyo, Japan

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
21 Nov 2009, 09:18
I agree. Should not we do something to clarify the xx%?? Since the box weighs x kg, people can assume that x=10 all through the calculation?



Manager
Joined: 24 Nov 2009
Posts: 106
WE 1: Manufacturing
WE 2: Analytics

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
29 Nov 2009, 02:44
the question is too confusing esp x  x% if we say x  x%ofx then it would be better or weight of (n1)th box = Wn – (Wn % of Wn) where Wn is the weight of nth box not easy to phrase



Current Student
Joined: 12 Apr 2010
Posts: 459
Location: Spain
Schools: Chicago (Booth)  Class of 2013
WE: Information Technology (Investment Banking)

Re: GMAT Diagnostic Test Question 45 [#permalink]
Show Tags
17 May 2010, 06:05
I just worked on this question and xx% also confused me. I used x as the original value (10) for all the boxes, not the previous weight.




Re: GMAT Diagnostic Test Question 45
[#permalink]
17 May 2010, 06:05



Go to page
1 2
Next
[ 30 posts ]




