<p>If three different circles are drawn on a piece of paper,
at most how many points can be common to all three??</p>
<p>I chose "SIx" as the answer. </p>
<h1>but the actually answer was quite differnt</h1>
<p>is there anyone who can explain me how it works?</p>
<p>two points.
two of the circles are like the ones in a venn diagram.
the third circle intersects at the two common points of the other two circles.</p>
<p>right?</p>
<p>2 points... </p>
<p>Because 2 circles can intersect at max 2 points, then the 3rd circle can go through either of the 2 points OR it can go through both of the 2 points( if u draw the circle appropriately) . Thus, there will be 2 points where all 3 circles intersect.</p>
<p>I say 3, because it says "in common," not "intersect".</p>
<p>If you draw the circles a bit like this: KIDS:</a> Jan Brennan Venn Diagram</p>
<p>There are 3 points that are common to all circles.</p>
<p>there is a problem with the word "common"....there can be an infinity number of points that can be common between three circles but they can only intersect at 2 points at their best....so i go with spidey</p>
<p>4 points. in book_worm's web link, you can see the 4 pts made by the middle circle.</p>
<p>^^ Where is the 4th point? I only see the three touching the gray center.</p>
<p>^sorry dolcevalse,i didn't get you....care to explain?</p>
<p>oops, i'm sorry! i didn't read the question carefully - it is 3, b/c 4 pts intersect, but only 3 are in common.</p>
<p>how many points can be common to ALL THREE...</p>
<p>The points selected must lie on the circumference of all 3 circles simultaneously.. and the max is this 2.. when u draw 2 intersecting circles, and the third circle passes through both their points of intersection.</p>
<p>The link that u gave- in that, the lowest point u talked about does not lie on the circumference of all three circles..</p>
<p>On that very diagram that u have given the link to, consider the circles A and B, and then a third circle passing through their 2 points of intersection. And u get the answer as 2 after seeing the diagram...
cos the question says common to ALL THREE.. means should lie on circumference of all 3, but look carefully and ur diagram doesnt have 3 such points.
A circle is only defined by the curved perimeter. u don't say a circle has a common point if another point lies within it's curved perimeter.. It would be so only if a 1-dimensional disk was mentioned, not a circle.</p>
<p>^ i didn't know there is a possibility of 1-dimensional disc :p lol....nice explanation though</p>
<p>So the answer is 2?</p>
<p>why i see no common point in bookworm's diagram lol?
yea i think its 2</p>
<p>To help people visualize
<a href="http://i33.tinypic.com/1zdsro3.jpg%5B/url%5D">http://i33.tinypic.com/1zdsro3.jpg</a></p>
<p>Also, the only other answer is infinity; too bad it's not an answer choice :P</p>
<p>that's a nice drawing there. i dont see why its infinity... there are only 2 points where all circles meet...</p>
<p>If they are all stacked up on top of each other. It would be infinity.</p>
<p>sry but CB Q's have no flaws
If three different circles</p>
<p>Oh. I must have skipped that part of the question :O!</p>
<p>yeah cant be infinity. but thanks for the demented drawing anhtimmy. :)</p>
