Averages and range (Edexcel GCSE Maths): Flashcards

Mean, median, and mode

How spread out the data is

Add all values and divide by number of values

$\text{Mean} = \frac{\text{Sum}}{\text{Number of values}}$

$\text{Sum} = \text{Mean} \times \text{Number of values}$

Middle value when arranged in order

Add them and divide by 2

Not affected by extreme values

Value that appears most often

Yes, if values appear equally often

All values appear same number of times

$\text{Range} = \text{Largest} - \text{Smallest}$

Put values in order from smallest to largest

Only when the question asks you to

Use $\text{Sum} = \text{Mean} \times \text{Number}$