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For Richer for Poorer

Age 14 to 16
Challenge Level


The mean is a type of average of a set of numbers.
The mean is the total of the numbers divided by how many numbers there are. 

Try starting with a specific example.

Group A is composed of people aged 2, 7, 11, 14 and 16 (average 10)
Group B is composed of people aged 5, 11, 12, 13 and 19 (average 12)

Investigate what happens to the averages when different members move from one group to the other.