Being collaborative

There are 300 NRICH Mathematical resources connected to Being collaborative
CD Heaven
problem

CD Heaven

Age
14 to 16
Challenge level
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All CD Heaven stores were given the same number of a popular CD to sell for £24. In their two week sale each store reduces the price of the CD by 25% ... How many CDs did the store sell at each price?
American Billions
problem

American Billions

Age
11 to 14
Challenge level
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Play the divisibility game to create numbers in which the first two digits make a number divisible by 2, the first three digits make a number divisible by 3...
Two and Two
problem

Two and Two

Age
7 to 16
Challenge level
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How many solutions can you find to this sum? Each of the different letters stands for a different number.
Why 24?
problem

Why 24?

Age
14 to 16
Challenge level
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Take any prime number greater than 3 , square it and subtract one. Working on the building blocks will help you to explain what is special about your results.
Dozens
problem

Dozens

Age
7 to 14
Challenge level
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Can you select the missing digit(s) to find the largest multiple?
Have you got it?
problem

Have you got it?

Age
11 to 14
Challenge level
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Can you explain the strategy for winning this game with any target?
Three cubes
problem

Three cubes

Age
14 to 16
Challenge level
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Can you work out the dimensions of the three cubes?
Birthday Cakes
problem

Birthday Cakes

Age
5 to 7
Challenge level
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Jack's mum bought some candles to use on his birthday cakes and when his sister was born, she used them on her cakes too. Can you use the information to find out when Kate was born?
Domino Sequences
problem

Domino Sequences

Age
5 to 7
Challenge level
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Find the next two dominoes in these sequences.
Cubes Cut into Four Pieces
problem

Cubes Cut into Four Pieces

Age
5 to 7
Challenge level
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Eight children each had a cube made from modelling clay. They cut them into four pieces which were all exactly the same shape and size. Whose pieces are the same? Can you decide who made each set?