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Trick or Treat

Age 7 to 11
Challenge Level Yellow starYellow star
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Emily and Tristan from St James' School answered the whole problem as follows:


I think the solution to this problem is that the most likly one to pick out is the mice because there are 9 mice and only 5 frogs and 4 worms, also to pick out at least one of each you would need to pick out 15 sweets because the first 9 could be mice and the next 5 you pick out could be frogs and after that you're definitely going to pick out a worm. As well as that if Trixie picked out a mouse there would still be 8 mice left so her brother is still more likely to pick out a mouse.

Well done to Connor from Eastwood Primary, pupils at Girton Glebe Primary, and Samm for also getting all or parts of the solution correct.



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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.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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