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## Circle of Children

Math brain teasers require computations to solve.

 Fun: (2.81) Difficulty: (1.27) Category: Math Submitted By: sk8ergrl

A number of children are standing in a circle. They are evenly spaced and the 7th child is directly opposite the 18th child. How many children are there altogether?

22; in half of the circle there are 11 children because 18-7=11. Multiply 11x2=22!
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 Posted by onlyeeyore on Jun 15, 2005 As usual I got this math teaser the long way. I've got to bone up on my algebra! Posted by Riddlerman on Jun 15, 2005 Algebra ain't anything to do with it. Just figure 10 kids either side of them (10) Double it as there are two sides (20), then add the two kids themselves (22) Bit EZ but i enjoyed it. Thanks. Posted by sk8ergrl on Jun 15, 2005 riddle is right. There is nothing to do with Algebra. I'm glad everyone seems to like it Posted by BrUnEttEcUtiE on Jun 15, 2005 We do these as bonus questions in school all the time! Posted by sweetime on Jun 15, 2005 my brain hurts i got 20 but i'm not entirely sure how Posted by tamjp on Jun 16, 2005 I needed the hint. but ast least then I got it! good one! Posted by PCDguitar on Jun 17, 2005 good 1 even tho i dont understand y u need to subtract 7 from 18 to get 11 to multiplay it by two? Posted by Question_Mark on Jun 17, 2005 Simple, but good. Posted by froggygg on Jun 22, 2005 Good teaser! Posted by amanduh05 on Jun 23, 2005 good 1 Posted by sk8ergrl on Mar 20, 2006 Thanx!!! Posted by tintiniscool on Aug 06, 2006 Fun! Posted by opqpop on Sep 11, 2010 I'm such an idiot. I figured out there were 10 kids on the right, and then figured out there were 6 kids before the 7th kid on the left, and hence 4 kids after the 18th kid to the left, for a total of 18 + 4 = 22 kids. Then I realized I could have just doubled 10 and added 2. Sigh I'm ashamed of my stupidity. Posted by doctapeppaman on Sep 27, 2012 The solution assumes that the children are arranged consecutively around the circle. Posted by Jimbo on Jun 03, 2013 The question may be considered by solving a simpler problem. If 4 kids stand in a circle, 1 is opposite 3 and 2 is opposite 4. The difference in position is always 2. Double it to find the number. So 18 - 7 = 11. 2 * 11 = 22. Posted by Jimbo on Jun 03, 2013 Good teaser BTW.