Combinations

There are 153 NRICH Mathematical resources connected to Combinations
Fruity Pairs
problem

Fruity pairs

Age
5 to 7
Challenge level
filled star empty star empty star

Which two items of fruit could Kate and Sam choose? Can you order the prices from lowest to highest?

Five Coins
problem

Five coins

Age
5 to 11
Challenge level
filled star filled star empty star
Ben has five coins in his pocket. How much money might he have?
The Puzzling Sweet Shop
problem

The puzzling sweet shop

Age
5 to 11
Challenge level
filled star filled star empty star
There were chews for 2p, mini eggs for 3p, Chocko bars for 5p and lollypops for 7p in the sweet shop. What could each of the children buy with their money?
Finding Fifteen
problem

Finding fifteen

Age
7 to 11
Challenge level
filled star filled star empty star
Tim had nine cards each with a different number from 1 to 9 on it. How could he have put them into three piles so that the total in each pile was 15?
Two Dice
problem

Two dice

Age
5 to 7
Challenge level
filled star empty star empty star
Find all the numbers that can be made by adding the dots on two dice.
1 Step 2 Step
problem

1 step 2 step

Age
11 to 14
Challenge level
filled star filled star empty star
Liam's house has a staircase with 12 steps. He can go down the steps one at a time or two at time. In how many different ways can Liam go down the 12 steps?
Teams
problem

Teams

Age
16 to 18
Challenge level
filled star empty star empty star
Two brothers belong to a club with 10 members. Four are selected for a match. Find the probability that both brothers are selected.
Cuisenaire Counting
problem

Cuisenaire counting

Age
5 to 7
Challenge level
filled star empty star empty star
Here are some rods that are different colours. How could I make a yellow rod using white and red rods?
Elevenses
problem

Elevenses

Age
11 to 14
Challenge level
filled star empty star empty star
How many pairs of numbers can you find that add up to a multiple of 11? Do you notice anything interesting about your results?
Mixed-up Socks
problem

Mixed-up socks

Age
5 to 7
Challenge level
filled star filled star empty star
Start with three pairs of socks. Now mix them up so that no mismatched pair is the same as another mismatched pair. Is there more than one way to do it?