List

Live Problems - Stage 3, 4 & 5

Each time students visit the NRICH site there will be some activities which are 'live'. That means we are inviting students to send us their solutions and we will publish a selection of them, along with their name and school's name. If you'd like to know more about what we're looking for, read this short article.

The last day for sending in solutions to these live problems is Monday 27 November.

Secondary Toughnuts
list

Secondary Toughnuts

Age
11 to 18
Challenge level
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These secondary problems have not yet been solved. Can you be the first?
Take Three From Five
problem
Favourite

Take Three From Five

Age
11 to 16
Challenge level
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Caroline and James pick sets of five numbers. Charlie tries to find three that add together to make a multiple of three. Can they stop him?

Cuboid challenge
problem
Favourite

Cuboid challenge

Age
11 to 16
Challenge level
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What's the largest volume of box you can make from a square of paper?

Slick Summing
problem
Favourite

Slick Summing

Age
14 to 16
Challenge level
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Watch the video to see how Charlie works out the sum. Can you adapt his method?