[David]

Don't know if anyone is interested in this, I'll post it and see what kind of reaction it gets. The history of this is that it was used to test candidates for an organisation in the 60's, and the time taken to work out the solution was the important bit, not the questions asked. It's just a bit of fun.

I thought it was the way the group of people worked together. to see if they can work as a team. as you say the task is irrelevant.

but I do know the answer

DAvid