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Resources tagged with Prime numbers similar to Strange Numbers:

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Challenge level: Challenge Level:1 Challenge Level:2 Challenge Level:3

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Broad Topics > Numbers and the Number System > Prime numbers

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Strange Numbers

Stage: 3 Challenge Level: Challenge Level:1

All strange numbers are prime. Every one digit prime number is strange and a number of two or more digits is strange if and only if so are the two numbers obtained from it by omitting either. . . .

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Different by One

Stage: 4 Challenge Level: Challenge Level:1

Make a line of green and a line of yellow rods so that the lines differ in length by one (a white rod)

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Sieve of Eratosthenes

Stage: 3 Challenge Level: Challenge Level:1

Follow this recipe for sieving numbers and see what interesting patterns emerge.

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Why 24?

Stage: 4 Challenge Level: Challenge Level:2 Challenge Level:2

Take any prime number greater than 3 , square it and subtract one. Working on the building blocks will help you to explain what is special about your results.

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Stars

Stage: 3 Challenge Level: Challenge Level:2 Challenge Level:2

Can you find a relationship between the number of dots on the circle and the number of steps that will ensure that all points are hit?

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An Introduction to Proof by Contradiction

Stage: 4 and 5

An introduction to proof by contradiction, a powerful method of mathematical proof.

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Factors and Multiples Game

Stage: 2 and 3 Challenge Level: Challenge Level:1

A game in which players take it in turns to choose a number. Can you block your opponent?

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Coins

Stage: 3 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

A man has 5 coins in his pocket. Given the clues, can you work out what the coins are?

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Factors and Multiples Puzzle

Stage: 3 Challenge Level: Challenge Level:1

A challenge that requires you to apply your knowledge of the properties of numbers. Can you fill all the squares on the board?


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