Ambiguous Ant Puzzle
Rob Eastaway and Alex Bellos set this puzzle in the Guardian in January 2016:
http://www.theguardian.com/science/2016/jan/18/can-you-solve-it-the-ants-on-a-stick-puzzle
Basic challenge is:
Ants are set up as follows on a 1 metre stick - distances in cm from the left:
- Alf (A) heading right, starting from 0,
- B (Bert) heading right from 20.2,
- C (Charlie) heading left from somewhere between B & C,
- D (Derek) heading right from 38.7,
- E (Ethel) heading right from 64.9,
- and F (Freda) heading left from 81.8