Stage: 3 Challenge Level: 
Each number will appear as a factor in 100!. So, for example 100! = 100x99x98x...where 22is a factor of 100, 2 is a factor of 98 and 25 is a factor of 96. Are there patterns to the powers of the number that appear as you consider each term of the factorial? Can this pattern be generalised for other numbers?
Factors and multiples. Prime factors. Working systematically. Workshop. Properties of numbers. smartphone. Modulus arithmetic. Divisibility. Multiplication & division. Factorials.
Published May 2002.
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