You may also like

problem icon

Forgotten Number

I have forgotten the number of the combination of the lock on my briefcase. I did have a method for remembering it...

problem icon

Man Food

Sam displays cans in 3 triangular stacks. With the same number he could make one large triangular stack or stack them all in a square based pyramid. How many cans are there how were they arranged?

problem icon

Sam Again

Here is a collection of puzzles about Sam's shop sent in by club members. Perhaps you can make up more puzzles, find formulas or find general methods.

Handshakes

Stage: 3 Challenge Level: Challenge Level:2 Challenge Level:2

If you were one of ten people at a party, how many times would you shake hands?
How many times would everyone else shake hands?
How could you use this to work out the total number of handshakes?
Check your method makes sense by trying some examples of small gatherings.