List

Codebreakers

Magnifying glass
problem
Favourite

Number Detective

Age
5 to 11
Challenge level
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Follow the clues to find the mystery number.

Coded hundred square
problem
Favourite

Coded hundred square

Age
7 to 11
Challenge level
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This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?
Mystery Matrix
problem
Favourite

Mystery Matrix

Age
7 to 11
Challenge level
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Can you fill in this table square? The numbers 2 -12 were used to generate it with just one number used twice.
Curious number
problem
Favourite

Curious number

Age
7 to 11
Challenge level
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Can you order the digits from 1-3 to make a number which is divisible by 3 so when the last digit is removed it becomes a 2-figure number divisible by 2, and so on?
Satisfying Four Statements
problem
Favourite

Satisfying Four Statements

Age
7 to 11
Challenge level
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Can you find any two-digit numbers that satisfy all of these statements?
Follow the numbers
problem
Favourite

Follow the numbers

Age
7 to 11
Challenge level
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What happens when you add the digits of a number then multiply the result by 2 and you keep doing this? You could try for different numbers and different rules.
What is Ziffle?
problem

What is Ziffle?

Age
7 to 11
Challenge level
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Can you work out what a ziffle is on the planet Zargon?