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#12 Factorial factory
Set by Mary Ellis
Mathematicians write 9! to represent the number “9 factorial”, which means 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1 = 362,880.
How many zeros will 10! end with?
How many zeros will 25! have at the end? (Careful, the answer isn’t five.)
How many zeros will 1066! finish with?
Solution next week
#11 Club shuffling
Solution
If the players are A, B, C and D then the possible games are: AB vs CD, AC vs BD and AD vs BC. So there are three games in total.
If A wins all their…
