Calling all maths detectives!
Can you solve the mysteries hidden in our carefully selected NRICH tasks?
Can you solve the mysteries hidden in our carefully selected NRICH tasks?
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Codebreakers
This article for Primary and Secondary teachers is all about the mathematics behind solving puzzles, unravelling mysteries and breaking codes.
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Count the digits
In this investigation we are going to count the number of 1s, 2s, 3s etc in numbers. Can you predict what will happen?
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I like ...
Mr Gilderdale is playing a game with his class. What rule might he have chosen? How would you test your idea?
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Secret number
Annie and Ben are playing a game with a calculator. What was Annie's secret number?
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What number?
I am less than 25. My ones digit is twice my tens digit. My digits add up to an even number.
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Coded hundred square
This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?
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Mystery matrix
Can you fill in this table square? The numbers 2 -12 were used to generate it with just one number used twice.
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Curious number
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?
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Satisfying four statements
Can you find any two-digit numbers that satisfy all of these statements?