Five Coins
Five Coins
Ben has five coins in his pocket.
How much money might he have? If possible, talk to someone else about your ideas.
What is the smallest amount of money he could have? How do you know?
What is the largest amount of money he could have? How do you know?
What if he still had five coins, but only 1ps and/or 2ps? How much might he have now?
Can you find all the possibilities?
How do you know you have found them all?
Why do this problem?
This activity is an interesting context in which to practise addition and subtraction, and it extends children's thinking to look at all possibilities. It requires a systematic approach and recording is key. It is also easy to extend for high-attaining pupils.
Possible approach
A simple but effective way to introduce this problem would be to suggest to the class that you have five coins in your pocket and you'd like them to find out how much money you might have. Give them a few minutes to talk to a partner and then ask some children to share their thoughts. Start to write up their suggestions on the board, for example by listing the five coins and the total. Ask them what the largest and smallest amounts would be (for example £10 and 5p when working in Sterling). At some point during this initial discussion, you may wish to list all the different coins for reference.
Key questions
Possible support
Having coins at the ready will be helpful for many pupils. Some may prefer to starting with just three coins and also just certain types of coins.
Possible extension
Five More Coins follows on from this task. It challenges children to find all the totals between 5p and £1 (when working in Sterling) that can be made with five coins.
You may also like
Let's Investigate Triangles
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?
