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Highest and Lowest

Put operations signs between the numbers 3 4 5 6 to make the highest possible number and lowest possible number.

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Make 100

Find at least one way to put in some operation signs (+ - x ÷) to make these digits come to 100.

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Four Goodness Sake

Use 4 four times with simple operations so that you get the answer 12. Can you make 15, 16 and 17 too?

Always, Sometimes or Never? Number

Stage: 2 Challenge Level: Challenge Level:1

Are the following statements always true, sometimes true or never true?

How do you know?


 

What about these more complex statements?

 
 
You could cut out the cards from this sheet (word, pdf) and arrange them in this grid.

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?
 
The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice. More information on many of our other activities can be found here.
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NRICH is part of the family of activities in the Millennium Mathematics Project.