Conundrum: 7, 8, 9, Venn!
In a Venn Diagram puzzle, there are three overlapping circles, marked A, B, and C. Each circle has a different rule about who or what can go inside. The challenge is to guess the rule for each circle. You can find a more detailed explanation of Venn Diagram puzzles, along with an example, here.
You’ve told me that there’s not enough math on this site, and I have listened. Each of the eight items below is a number.
Have you figured out one of the rules? Two? All three? Feel free to post whatever you’ve got in the comments below. Just tell us which circle you’re solving, and what the rule is.
Enjoy!
UPDATE: Circles B and C solved by Kenneth W. Davis. See comments for all answers.
May 2nd, 2007 at 7:21 am
Circle B holds primes?
May 2nd, 2007 at 7:23 am
Circle C holds Fibonacci numbers?
May 2nd, 2007 at 9:46 am
Correct on both counts! Very nicely done!
I thought Circle C would be the tricky one of this batch.
(I always try to put the circles in increasing order of difficulty, though I’m not always the best judge of relative difficulty.)
May 2nd, 2007 at 2:41 pm
I doubt this is the answer to A, but I noticed that if you start with 17 and add four you get 21 and then add four again you get 25 and if you keep adding 4 you’ll get to 89…
May 2nd, 2007 at 3:53 pm
Oh, that’s a nice catch.
However, 13 would also be in this series.
Keep trying!
May 8th, 2007 at 1:04 pm
Circle A holds numbers that have three syllables.