Always, Sometimes or Never? Number
Are the following statements always true, sometimes true or never true?
How do you know?
Can you find examples or counter-examples for each one?
For the 'sometimes' cards can you explain when they are true? Or rewrite them so that they are always true or never true?
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The sum of three numbers is odd |
If you add 1 to an odd number you get an even number |
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Multiples of 5 end in a 5 |
If you add two odd numbers you get an odd number |
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If you add a multiple of 10 to a multiple of 5 the answer is a multiple of 5 |
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What about these more complex statements?
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When you multiply two numbers you will always get a bigger number |
If you add a number to 5 your answer will be bigger than 5 |
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A square number has an even number of factors |
The sum of three consecutive numbers is divisible by 3 |
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Dividing a whole number by a half makes it twice as big |
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You could cut out the statement cards and arrange them in this grid.
Alternatively, you may like to try out your ideas using the interactivities below:
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Round and Round the Circle
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