January 19, 2019 January 19, 2019 07:00 AM PST 09:00 AM PST Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT. January 20, 2019 January 20, 2019 07:00 AM PST 07:00 AM PST Get personalized insights on how to achieve your Target Quant Score.
Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 52294

Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
14 Nov 2017, 22:45
Question Stats:
15% (01:04) correct 85% (00:58) wrong based on 162 sessions
HideShow timer Statistics



Manager
Joined: 05 Dec 2016
Posts: 243
Concentration: Strategy, Finance

Re: Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
15 Nov 2017, 00:09
Each pair forms up only one possible diameter when points are located at strictly opposite sides. If we are considering "at most" extreme case then all ponts should be evenly distributed on the circumference of the circle, and since we have 17 points, only 16 out of 17 can be placed opposite each other and 17th one would not have a pair. So there should be 8 possible diameteres at most however if we assume that there could be an overlap, then 17th point can overlap to any other and form up another 9th diameter. OR maybe some more tricker logic lies behind the correct reasoning of subject problem



Director
Joined: 09 Mar 2017
Posts: 522
Location: India
Concentration: Marketing, Organizational Behavior
WE: Information Technology (Computer Software)

Re: Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
15 Nov 2017, 08:18
Bunuel wrote: Seventeen different points are to be located on the circumference of a circle and each point is to be connected to all other points by line segments. At most, how many of the segments thus formed can be diameters of a circle?
(A) 8 (B) 9 (C) 16 (D) 17 (E) 34 imo A  8 only if two points are exactly opposite to each other,the line joining them would be diameter. 17 points have such 16 points and hence 8 pairs. One point has no point to be connected to as diameter.
_________________
 "Trust the timing of your life" Hit Kudus if this has helped you get closer to your goal, and also to assist others save time. Tq



Director
Joined: 27 May 2012
Posts: 667

Re: Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
28 Oct 2018, 12:28
Bunuel wrote: Seventeen different points are to be located on the circumference of a circle and each point is to be connected to all other points by line segments. At most, how many of the segments thus formed can be diameters of a circle?
(A) 8 (B) 9 (C) 16 (D) 17 (E) 34 Dear Moderator, Kindly provide the Official explanation for this one, seems as though the Answer should be A. Here is a similar sum , using the same logic , accordingly the answer here should be A IMO. Please kindly explain how the answer is C. Thank you. https://gmatclub.com/forum/eachofthe ... 02190.html
_________________
 Stne



Manager
Joined: 20 Jun 2018
Posts: 73
Location: India

Re: Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
28 Oct 2018, 19:33
Hey Bunuel please provide an explanation for this. I think the answer should be A
_________________
PLEASE GIVE KUDOS IF YOU WERE ABLE TO SOLVE THE QUESTION. THANK YOU.



Manager
Joined: 21 Jun 2017
Posts: 207
Concentration: Finance, Economics
WE: Corporate Finance (Commercial Banking)

Re: Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
03 Nov 2018, 06:03
Hi ! Can you please explain the OA ? GMATinsight
_________________
Even if it takes me 30 attempts, I am determined enough to score 740+ in my 31st attempt. This is it, this is what I have been waiting for, now is the time to get up and fight, for my life is 100% my responsibility.
Dil ye Ziddi hai !!!



CEO
Status: GMATINSIGHT Tutor
Joined: 08 Jul 2010
Posts: 2726
Location: India
GMAT: INSIGHT
WE: Education (Education)

Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
Updated on: 03 Nov 2018, 21:55
ShankSouljaBoi wrote: Hi ! Can you please explain the OA ? GMATinsightQuote: Seventeen different points are to be located on the circumference of a circle and each point is to be connected to all other points by line segments. At most, how many of the segments thus formed can be diameters of a circle?
(A) 8 (B) 9 (C) 16 (D) 17 (E) 34 ShankSouljaBoiCONCEPT: A diameter is a line joining two diametrically opposite points on the circumference. i.e. a Diameter requires joining two pointsSince we have 17 points so we need to see how many pairs of points can we make Total pairs of two points = Greatest integer of (17/2) = [17/2] = 8 i.e. There will be 8 distinct diagonalsBut since every point is being joined with every other point here therefore total such lines will be 16 as every diagonal will be drawn two e.g. We will draw a line originating from point 1 to point 9 and then next attempt will be to draw line originating from point 9 and connecting point 1i.e. Same diameter drawn twice Hence, total Such lines which become diameter = 8*2 = 16 Answer: Option C
Attachments
Screenshot 20181104 at 11.07.57 AM.png [ 308.58 KiB  Viewed 580 times ]
_________________
Prosper!!! GMATinsight Bhoopendra Singh and Dr.Sushma Jha email: info@GMATinsight.com I Call us : +919999687183 / 9891333772 Online OneonOne Skype based classes and Classroom Coaching in South and West Delhi http://www.GMATinsight.com/testimonials.html
ACCESS FREE GMAT TESTS HERE:22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION
Originally posted by GMATinsight on 03 Nov 2018, 21:50.
Last edited by GMATinsight on 03 Nov 2018, 21:55, edited 1 time in total.



CEO
Status: GMATINSIGHT Tutor
Joined: 08 Jul 2010
Posts: 2726
Location: India
GMAT: INSIGHT
WE: Education (Education)

Re: Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
03 Nov 2018, 21:54
stne wrote: Bunuel wrote: Seventeen different points are to be located on the circumference of a circle and each point is to be connected to all other points by line segments. At most, how many of the segments thus formed can be diameters of a circle?
(A) 8 (B) 9 (C) 16 (D) 17 (E) 34 Dear Moderator, Kindly provide the Official explanation for this one, seems as though the Answer should be A. Here is a similar sum , using the same logic , accordingly the answer here should be A IMO. Please kindly explain how the answer is C. Thank you. https://gmatclub.com/forum/eachofthe ... 02190.html stne and ShbmPlease pay attention to the language of question and then see the explanation here. The question says, each point is to be connected to all other points by line segments and then At most, how many of the segments thus formed can be diameters of a circleCheck the highlighted, Bold and Italic part which states how many such segments will be diameter that is each segment is to be counted separately irrespective of duplication of the same line therefore, e.g. We will draw a line originating from point 1 to point 9 and then next attempt will be to draw line originating from point 9 and connecting point 1i.e. Same diameter drawn twice hence 8 diameters will be counted 16 times CONCEPT: A diameter is a line joining two diametrically opposite points on the circumference. i.e. a Diameter requires joining two pointsSince we have 17 points so we need to see how many pairs of points can we make Total pairs of two points = Greatest integer of (17/2) = [17/2] = 8 i.e. There will be 8 distinct diagonalsBut since every point is being joined with every other point here therefore total such lines will be 16 as every diagonal will be drawn two e.g. We will draw a line originating from point 1 to point 9 and then next attempt will be to draw line originating from point 9 and connecting point 1i.e. Same diameter drawn twice Hence, total Such lines which become diameter = 8*2 = 16 Answer: Option C I hope this helps!!!
_________________
Prosper!!! GMATinsight Bhoopendra Singh and Dr.Sushma Jha email: info@GMATinsight.com I Call us : +919999687183 / 9891333772 Online OneonOne Skype based classes and Classroom Coaching in South and West Delhi http://www.GMATinsight.com/testimonials.html
ACCESS FREE GMAT TESTS HERE:22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION



VP
Joined: 18 Aug 2017
Posts: 1246
Location: India
Concentration: Sustainability, Marketing
WE: Marketing (Energy and Utilities)

Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
05 Nov 2018, 05:33
GMATinsight: sir, quoting your line below: concept: "A diameter is a line joining two diametrically opposite points on the circumference. i.e. a Diameter requires joining two points" For a diameter to be valid on a circle it has to pass through the center as well as 'd=r*2', by your above statement it seems to give definition of a chord of circle... the word 'center' is missing from your statement. For the question we can also solve it as below: First drawing a circle and marking 17 points on opposite sides of the circle circumference, we would be left with only 1 point which won't be having any pair, total set of pairs would be 8 or say 16 segments ' diameter' thus be formed on the circle which are all passing through center of the circle, Had the question not specified the word " diameter ' "how many of the segments thus formed on the circle using 17 points" in that case answer would have been undefined as the position of 17 points wouldn't have be sure.....
_________________
If you liked my solution then please give Kudos. Kudos encourage active discussions.



CEO
Status: GMATINSIGHT Tutor
Joined: 08 Jul 2010
Posts: 2726
Location: India
GMAT: INSIGHT
WE: Education (Education)

Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
06 Nov 2018, 06:36
Archit3110 wrote: GMATinsight: sir, quoting your line below: concept: "A diameter is a line joining two diametrically opposite points on the circumference. i.e. a Diameter requires joining two points" For a diameter to be valid on a circle it has to pass through the center as well as 'd=r*2', by your above statement it seems to give definition of a chord of circle... the word 'center' is missing from your statement. For the question we can also solve it as below: First drawing a circle and marking 17 points on opposite sides of the circle circumference, we would be left with only 1 point which won't be having any pair, total set of pairs would be 8 or say 16 segments ' diameter' thus be formed on the circle which are all passing through center of the circle, Had the question not specified the word " diameter ' "how many of the segments thus formed on the circle using 17 points" in that case answer would have been undefined as the position of 17 points wouldn't have be sure..... Archit3110The highlighted part "Diametrically opposite points", by definition, ensures that the line passes through the centre. Refer: http://www.mathwords.com/d/diametrically_opposed.htm
_________________
Prosper!!! GMATinsight Bhoopendra Singh and Dr.Sushma Jha email: info@GMATinsight.com I Call us : +919999687183 / 9891333772 Online OneonOne Skype based classes and Classroom Coaching in South and West Delhi http://www.GMATinsight.com/testimonials.html
ACCESS FREE GMAT TESTS HERE:22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION



VP
Joined: 18 Aug 2017
Posts: 1246
Location: India
Concentration: Sustainability, Marketing
WE: Marketing (Energy and Utilities)

Re: Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
06 Nov 2018, 10:38
GMATinsight: Okay got it sir.. thanks.
_________________
If you liked my solution then please give Kudos. Kudos encourage active discussions.



Manager
Joined: 30 May 2017
Posts: 135
Location: United States
GPA: 3.57

Re: Seventeen different points are to be located on the circumference of a
[#permalink]
Show Tags
17 Jan 2019, 03:08
Bunuel wrote: Seventeen different points are to be located on the circumference of a circle and each point is to be connected to all other points by line segments. At most, how many of the segments thus formed can be diameters of a circle?
(A) 8 (B) 9 (C) 16 (D) 17 (E) 34 I personally think the answer to the question is ambiguous. It can be 8 or 16 depending on how you count line segment. I do not see official GMAT asking a question with ambiguous answers.
_________________
Kindly press the +1Kudos if you like the explanation. Thanks a lot!!!




Re: Seventeen different points are to be located on the circumference of a &nbs
[#permalink]
17 Jan 2019, 03:08






