Averages from tables 2 (Edexcel GCSE Maths): Flashcards

Data grouped into ranges, not individual values

Don't know exact data values within intervals

Class interval with highest frequency

Find highest frequency in frequency column

Class interval containing the median value

$(n + 1) \div 2$

Mid-point method

$(lowest + highest) \div 2$

Frequency multiplied by mid-point

$\frac{\text{Total } f \times x}{\text{Total frequency}}$

Assumes all values equal mid-point, may not be true

As an estimate