Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized for You
we will pick new questions that match your level based on your Timer History
Track Your Progress
every week, we’ll send you an estimated GMAT score based on your performance
Practice Pays
we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
It appears that you are browsing the GMAT Club forum unregistered!
Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club
Registration gives you:
Tests
Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.
Applicant Stats
View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more
Books/Downloads
Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!
Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:
In the figure shown, the circle has center O and radius 50 [#permalink]
03 Jan 2011, 17:18
4
This post was BOOKMARKED
00:00
A
B
C
D
E
Difficulty:
95% (hard)
Question Stats:
40% (02:18) correct
60% (01:12) wrong based on 230 sessions
Attachment:
Circle.png [ 14.99 KiB | Viewed 9808 times ]
In the figure shown, the circle has center O and radius 50, and point P has coordinates (50,0). If point Q (not shown) is on the circle, what is the length of line segment PQ ?
(1) The x-coordinate of point Q is – 30. (2) The y-coordinate of point Q is – 40.
Re: figure shown, the circle has center O and radius 50 [#permalink]
04 Jan 2011, 02:03
7
This post received KUDOS
Expert's post
In the figure shown, the circle has center O and radius 50, and point P has coordinates (50,0). If point Q (not shown) is on the circle, what is the length of line segment PQ ?
Note that we are told that point Q is on the circle. Also as the radius of the circle is 50 then for any point (x,y) on the circle \(x^2+y^2=50^2\) (check for more here: math-coordinate-geometry-87652.html) Look at the diagram:
Attachment:
Circle.png [ 13.28 KiB | Viewed 9780 times ]
(1) The x-coordinate of point Q is – 30 --> point Q can be either on the position of Q1 or Q2 on the diagram, but in any case the distance between P and Q is the same --> for point Q: \((-30)^2+y^2=50^2\) --> \(y^2=20*80=40^2\), so \(CQ^2=y^2=40^2\) (no matter where Q actually is on Q1 or Q2) --> PQ which is the hypotenuse in PQC is equal to \(PQ^2=PC^2+CQ^2=80^2+40^2\) --> \(PQ=40\sqrt{5}\). Sufficient.
(2) The y-coordinate of point Q is – 40 --> point Q can be either on the position of Q2 or Q3 on the diagram, and the distance between P and Q will be different for theses cases. Not sufficient.
Re: figure shown, the circle has center O and radius 50 [#permalink]
23 Feb 2012, 00:48
How doe we know that P lies on the diameter ? As per question, position of P relative to centre is not known. So how is it assumed that P is on the diameter? Wouldn't it change answer ?
Re: figure shown, the circle has center O and radius 50 [#permalink]
23 Feb 2012, 01:24
Expert's post
deepo85 wrote:
How doe we know that P lies on the diameter ? As per question, position of P relative to centre is not known. So how is it assumed that P is on the diameter? Wouldn't it change answer ?
Since the circle is centered at the origin and has the radius 50, then point P(50,0) must lie on a circle.
Re: figure shown, the circle has center O and radius 50 [#permalink]
03 Aug 2013, 06:52
Bunuel wrote:
In the figure shown, the circle has center O and radius 50, and point P has coordinates (50,0). If point Q (not shown) is on the circle, what is the length of line segment PQ ?
Note that we are told that point Q is on the circle. Also as the radius of the circle is 50 then for any point (x,y) on the circle \(x^2+y^2=50^2\) (check for more here: math-coordinate-geometry-87652.html) Look at the diagram:
Attachment:
Circle.png
(1) The x-coordinate of point Q is – 30 --> point Q can be either on the position of Q1 or Q2 on the diagram, but in any case the distance between P and Q is the same --> for point Q: \((-30)^2+y^2=50^2\) --> \(y^2=20*80=40^2\), so \(CQ^2=y^2=40^2\) (no matter where Q actually is on Q1 or Q2) --> PQ which is the hypotenuse in PQC is equal to \(PQ^2=PC^2+CQ^2=80^2+40^2\) --> \(PQ=40\sqrt{5}\). Sufficient.
(2) The y-coordinate of point Q is – 40 --> point Q can be either on the position of Q2 or Q3 on the diagram, and the distance between P and Q will be different for theses cases. Not sufficient.
Answer: A.
why cannot the point Q have coordinates (-30,0) in this case point Q will lie on the Diameter of the circle and the distance from point P will be 80, so aren't we getting two cases for A? What am I missing here? Can anybody assist? _________________
Re: figure shown, the circle has center O and radius 50 [#permalink]
03 Aug 2013, 07:01
Expert's post
stne wrote:
Bunuel wrote:
In the figure shown, the circle has center O and radius 50, and point P has coordinates (50,0). If point Q (not shown) is on the circle, what is the length of line segment PQ ?
Note that we are told that point Q is on the circle. Also as the radius of the circle is 50 then for any point (x,y) on the circle \(x^2+y^2=50^2\) (check for more here: math-coordinate-geometry-87652.html) Look at the diagram:
Attachment:
Circle.png
(1) The x-coordinate of point Q is – 30 --> point Q can be either on the position of Q1 or Q2 on the diagram, but in any case the distance between P and Q is the same --> for point Q: \((-30)^2+y^2=50^2\) --> \(y^2=20*80=40^2\), so \(CQ^2=y^2=40^2\) (no matter where Q actually is on Q1 or Q2) --> PQ which is the hypotenuse in PQC is equal to \(PQ^2=PC^2+CQ^2=80^2+40^2\) --> \(PQ=40\sqrt{5}\). Sufficient.
(2) The y-coordinate of point Q is – 40 --> point Q can be either on the position of Q2 or Q3 on the diagram, and the distance between P and Q will be different for theses cases. Not sufficient.
Answer: A.
why cannot the point Q have coordinates (-30,0) in this case point Q will lie on the Diameter of the circle and the distance from point P will be 80, so aren't we getting two cases for A? What am I missing here? Can anybody assist?
You are forgetting that if Q is (-30,0), then the point will no longer be ON the circle. It will be IN the circle. _________________
Re: figure shown, the circle has center O and radius 50 [#permalink]
03 Aug 2013, 08:50
mau5 wrote:
stne wrote:
Bunuel wrote:
In the figure shown, the circle has center O and radius 50, and point P has coordinates (50,0). If point Q (not shown) is on the circle, what is the length of line segment PQ ?
Note that we are told that point Q is on the circle. Also as the radius of the circle is 50 then for any point (x,y) on the circle \(x^2+y^2=50^2\) (check for more here: math-coordinate-geometry-87652.html) Look at the diagram:
Attachment:
Circle.png
(1) The x-coordinate of point Q is – 30 --> point Q can be either on the position of Q1 or Q2 on the diagram, but in any case the distance between P and Q is the same --> for point Q: \((-30)^2+y^2=50^2\) --> \(y^2=20*80=40^2\), so \(CQ^2=y^2=40^2\) (no matter where Q actually is on Q1 or Q2) --> PQ which is the hypotenuse in PQC is equal to \(PQ^2=PC^2+CQ^2=80^2+40^2\) --> \(PQ=40\sqrt{5}\). Sufficient.
(2) The y-coordinate of point Q is – 40 --> point Q can be either on the position of Q2 or Q3 on the diagram, and the distance between P and Q will be different for theses cases. Not sufficient.
Answer: A.
why cannot the point Q have coordinates (-30,0) in this case point Q will lie on the Diameter of the circle and the distance from point P will be 80, so aren't we getting two cases for A? What am I missing here? Can anybody assist?
You are forgetting that if Q is (-30,0), then the point will no longer be ON the circle. It will be IN the circle.
Correct! Realized this just after I posted it. Although couldn't it have been more clearer if it was mentioned that point Q lies on the circumference of the circle? Just ON the circle can also mean anywhere in the circle,can it not? _________________
Re: figure shown, the circle has center O and radius 50 [#permalink]
03 Aug 2013, 08:54
Expert's post
stne wrote:
Correct! Realized this just after I posted it. Although couldn't it have been more clearer if it was mentioned that point Q lies on the circumference of the circle? Just ON the circle can also mean anywhere in the circle,can it not?
No.A point lying on the circumference or a point lying on the circle is the same thing.IF it is on the circle, it can't be anywhere else. _________________
Re: figure shown, the circle has center O and radius 50 [#permalink]
03 Aug 2013, 09:01
mau5 wrote:
stne wrote:
Correct! Realized this just after I posted it. Although couldn't it have been more clearer if it was mentioned that point Q lies on the circumference of the circle? Just ON the circle can also mean anywhere in the circle,can it not?
No.A point lying on the circumference or a point lying on the circle is the same thing.IF it is on the circle, it can't be anywhere else.
Let me just cement my understanding,ON and circumference is the same thing, So if it says that a point lies on the circle, it always means that the point lies on the circumference, is that correct. _________________
Re: figure shown, the circle has center O and radius 50 [#permalink]
03 Aug 2013, 09:05
1
This post received KUDOS
Expert's post
stne wrote:
mau5 wrote:
stne wrote:
Correct! Realized this just after I posted it. Although couldn't it have been more clearer if it was mentioned that point Q lies on the circumference of the circle? Just ON the circle can also mean anywhere in the circle,can it not?
No.A point lying on the circumference or a point lying on the circle is the same thing.IF it is on the circle, it can't be anywhere else.
Let me just cement my understanding,ON and circumference is the same thing, So if it says that a point lies on the circle, it always means that the point lies on the circumference, is that correct.
Yes, that is correct.Any point on the circle is a point on the circumference. _________________
Re: figure shown, the circle has center O and radius 50 [#permalink]
14 Apr 2014, 23:46
HI Bunnel,
I am not clear about second statement.
(2) The y-coordinate of point Q is – 40 --> point Q can be either on the position of Q2 or Q3 on the diagram, and the distance between P and Q will be different for theses cases. Not sufficient.
Re: figure shown, the circle has center O and radius 50 [#permalink]
15 Apr 2014, 00:12
Expert's post
pawankumargadiya wrote:
HI Bunnel,
I am not clear about second statement.
(2) The y-coordinate of point Q is – 40 --> point Q can be either on the position of Q2 or Q3 on the diagram, and the distance between P and Q will be different for theses cases. Not sufficient.
Please clarify.
Look at the diagram below:
Attachment:
Untitled.png [ 11.5 KiB | Viewed 4290 times ]
We are told that the y-coordinate of point Q is -40, so it's either on the position of Q2 or Q3. As you can see these different positions give different distances for PQ (blue and green lines).
Re: In the figure shown, the circle has center O and radius 50 [#permalink]
04 Feb 2016, 18:06
oh man..just made a crucial mistake and mistook x for y and y for x.
if we know X, we then can have 2 points - positive Y and negative Y. in either case, the distance from Q to P will be the same, since the points would be a reflection, and the distance would be the same.
knowing for X - we can answer the question. knowing for Y - we can't answer, since X can be either positive or negative. 2 different values. thus, A is sufficient.
gmatclubot
Re: In the figure shown, the circle has center O and radius 50
[#permalink]
04 Feb 2016, 18:06
The “3 golden nuggets” of MBA admission process With ten years of experience helping prospective students with MBA admissions and career progression, I will be writing this blog through...
You know what’s worse than getting a ding at one of your dreams schools . Yes its getting that horrid wait-listed email . This limbo is frustrating as hell . Somewhere...