Combinations

A man has 5 coins in his pocket. Given the clues, can you work out what the coins are?

Four friends must cross a bridge. How can they all cross it in just 17 minutes?

How can you arrange these 10 matches in four piles so that when you move one match from three of the piles into the fourth, you end up with the same arrangement?

How many arm-wrestles will there be in the royal arm wrestling championship?

How many ways are there to make 11p using 1p, 2p and 5p coins?

How many different shapes can you make by putting four right- angled isosceles triangles together?

Try grouping the dominoes in the ways described. Are there any left over each time? Can you explain why?

How many different ways can you find to join three equilateral triangles together? Can you convince us that you have found them all?

Using only the red and white rods, how many different ways are there to make up the other rods?

Squares of the type shown are sewn together to make a quilt. How many different quilts can be made?