Exploring and noticing

There are 319 NRICH Mathematical resources connected to Exploring and noticing
Magic Matrix
problem

Magic Matrix

Age
7 to 11
Challenge level
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Find out why these matrices are magic. Can you work out how they were made? Can you make your own Magic Matrix?
Route to infinity
problem

Route to infinity

Age
11 to 14
Challenge level
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Can you describe this route to infinity? Where will the arrows take you next?
Multiples Grid
problem

Multiples Grid

Age
7 to 11
Challenge level
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What do the numbers shaded in blue on this hundred square have in common? What do you notice about the pink numbers? How about the shaded numbers in the other squares?
Tricky Triangles
problem

Tricky Triangles

Age
5 to 7
Challenge level
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Use the three triangles to fill these outline shapes. Perhaps you can create some of your own shapes for a friend to fill?
There's always One isn't there
problem

There's always One isn't there

Age
14 to 16
Challenge level
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Take any pair of numbers, say 9 and 14. Take the larger number, fourteen, and count up in 14s. Then divide each of those values by the 9, and look at the remainders.
Sticks and Triangles
problem

Sticks and Triangles

Age
7 to 11
Challenge level
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Using different numbers of sticks, how many different triangles are you able to make? Can you make any rules about the numbers of sticks that make the most triangles?
Royal Arm Wrestling
problem

Royal Arm Wrestling

Age
11 to 14
Challenge level
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How many arm-wrestles will there be in the royal arm wrestling championship?
Domino Sorting
problem

Domino Sorting

Age
5 to 7
Challenge level
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Try grouping the dominoes in the ways described. Are there any left over each time? Can you explain why?
Magic potting sheds
problem

Magic potting sheds

Age
11 to 16
Challenge level
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Mr McGregor has a magic potting shed. Overnight, the number of plants in it doubles. He'd like to put the same number of plants in each of three gardens, planting one garden each day. Can he do it?
Brush Loads
problem

Brush Loads

Age
7 to 11
Challenge level
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How can you arrange the 5 cubes so that you need the smallest number of Brush Loads of paint to cover them? Try with other numbers of cubes as well.