Combinations

There are 149 NRICH Mathematical resources connected to Combinations
Football crazy Hockey mad
problem

Football crazy Hockey mad

Age
11 to 14
Challenge level
filled star empty star empty star
In a league of 5 football teams which play in a round robin tournament show that it is possible for all five teams to be league leaders.
Chances are
problem

Chances are

Age
14 to 16
Challenge level
filled star empty star empty star
Which of these games would you play to give yourself the best possible chance of winning a prize?
Flight of the Flibbins
problem

Flight of the Flibbins

Age
11 to 14
Challenge level
filled star filled star empty star
Blue Flibbins are so jealous of their red partners that they will not leave them on their own with any other bue Flibbin. What is the quickest way of getting the five pairs of Flibbins safely to the new planet?
Pattern of islands
problem

Pattern of islands

Age
11 to 14
Challenge level
filled star filled star empty star
In how many distinct ways can six islands be joined by bridges so that each island can be reached from every other island...
Dicing with numbers
problem

Dicing with numbers

Age
11 to 14
Challenge level
filled star empty star empty star
In how many ways can you arrange three dice side by side on a surface so that the sum of the numbers on each of the four faces (top, bottom, front and back) is equal?
Domino tetrads
problem

Domino tetrads

Age
11 to 14
Challenge level
filled star filled star filled star
Is it possible to use all 28 dominoes arranging them in squares of four? What patterns can you see in the solution(s)?
Child's Play
problem

Child's Play

Age
7 to 11
Challenge level
filled star filled star empty star
A toy has a regular tetrahedron, a cube and a base with triangular and square hollows. If you fit a shape into the correct hollow a bell rings. How many times does the bell ring in a complete game?
Factoring a million
problem

Factoring a million

Age
14 to 16
Challenge level
filled star filled star filled star
In how many ways can the number 1 000 000 be expressed as the product of three positive integers?
Sam Again
problem

Sam Again

Age
11 to 14
Challenge level
filled star empty star empty star
Here is a collection of puzzles about Sam's shop sent in by club members. Perhaps you can make up more puzzles, find formulas or find general methods.
Human Food
problem

Human Food

Age
7 to 14
Challenge level
filled star empty star empty star
Sam displays cans in 3 triangular stacks. With the same number he could make one large triangular stack or stack them all in a square based pyramid. How many cans are there how were they arranged?