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Puzzles #50-52: Can you crack these festive mathematical puzzles?

Maths and colouring? Get out your pens to solve our bumper Christmas BrainTwister, along with more holiday puzzles and the answer to puzzle #49

By Peter Rowlett, Phil Lloyd, TD Dang and Matthew Scroggs

11 December 2024

New Scientist. Science news and long reads from expert journalists, covering developments in science, technology, health and the environment on the website and the magazine.

#50 Puzzle-by-numbers

Set by Matthew Scroggs and TD Dang

Solve these six puzzles, then find each region of the image below that contains one of the answers and colour it brown. Each answer may appear more than once.

1. Holly added up the first four odd numbers. What total did she get?

2. Holly added up the first m odd numbers to get a total of 441. What is m?

3. The number n! is calculated by multiplying together all the integers from 1 to n. How many zeros does the number 10! end with?

4. How many zeros does…

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