You may also like

problem icon

Human 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.

problem icon

Hot Pursuit

I added together the first 'n' positive integers and found that my answer was a 3 digit number in which all the digits were the same...

Forgotten Number

Age 11 to 14 Challenge Level:

1 factorial = 1
2 factorial = 1 x 2 = 2
3 factorial = 1 x 2 x 3 = 6
4 factorial = 1 x 2 x 3 x 4 = 24
5 factorial = 1 x 2 x 3 x 4 x 5 = 120...

The triangle numbers are 1, 3, 6, 10, 15, 21...