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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?

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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.

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Picturing Triangle Numbers

Triangle numbers can be represented by a triangular array of squares. What do you notice about the sum of identical triangle numbers?

Forgotten Number

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

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...