Combinations

There are 149 NRICH Mathematical resources connected to Combinations
Noah
problem

Noah

Age
5 to 7
Challenge level
filled star filled star empty star
Noah saw 12 legs walk by into the Ark. How many creatures did he see?
Teddy Town
problem

Teddy Town

Age
5 to 11
Challenge level
filled star filled star empty star
There are nine teddies in Teddy Town - three red, three blue and three yellow. There are also nine houses, three of each colour. Can you put them on the map of Teddy Town according to the rules?
Halloween Investigation
problem

Halloween Investigation

Age
7 to 11
Challenge level
filled star empty star empty star
Ana and Ross looked in a trunk in the attic. They found old cloaks and gowns, hats and masks. How many possible costumes could they make?
Penta Place
problem

Penta Place

Age
7 to 11
Challenge level
filled star filled star filled star
Penta people, the Pentominoes, always build their houses from five square rooms. I wonder how many different Penta homes you can create?
Let's Investigate Triangles
problem

Let's Investigate Triangles

Age
5 to 7
Challenge level
filled star empty star empty star
Vincent and Tara are making triangles with the class construction set. They have a pile of strips of different lengths. How many different triangles can they make?
Making Cuboids
problem

Making Cuboids

Age
7 to 11
Challenge level
filled star filled star empty star
Let's say you can only use two different lengths - 2 units and 4 units. Using just these 2 lengths as the edges how many different cuboids can you make?
Sweets in a box
problem

Sweets in a box

Age
7 to 11
Challenge level
filled star empty star empty star
How many different shaped boxes can you design for 36 sweets in one layer? Can you arrange the sweets so that no sweets of the same colour are next to each other in any direction?
Bean Bags for Bernard's Bag
problem

Bean Bags for Bernard's Bag

Age
7 to 11
Challenge level
filled star filled star empty star
How could you put eight beanbags in the hoops so that there are four in the blue hoop, five in the red and six in the yellow? Can you find all the ways of doing this?
Ice Cream
problem

Ice Cream

Age
7 to 11
Challenge level
filled star filled star filled star
You cannot choose a selection of ice cream flavours that includes totally what someone has already chosen. Have a go and find all the different ways in which seven children can have ice cream.
It Figures
problem

It Figures

Age
7 to 11
Challenge level
filled star filled star empty star
Suppose we allow ourselves to use three numbers less than 10 and multiply them together. How many different products can you find? How do you know you've got them all?