Puzzle page

Puzzle No. 3 - birth dates

Here is this issue's puzzle.

Solution to Puzzle No. 2 - carnivorous beetles

The following people submitted correct answers:
- Jon McLoone, Wolfram Research Europe Ltd
- Roger Stratford, Cambridge, England.

Rectangle/Triangle problem

Following on from this issue's article "The life and numbers of Fibonacci", the solution to this problem is the golden section but why?

Optimal stopping

Following on from this issue's article "Mathematics, marriage and finding somewhere to eat", this page on the optimal stopping problem takes you through the derivation of the "37% rule" step-by-step.