The main averages, which can also be referred to as measures of central tendency, are the mean, mode and median. Robert is preparing for his Mathematics GCSE exams. Each paper is marked out of 100.

JEFF: Let’s start with the ‘mean’ score. JANINE ... JANINE: We can even find the ‘median,' Jeff. Just look at our ordered scores and it’s the one right in the middle, which is six!

For a single attribute distribution, the formula for skewness ... The relative values of the mean, median, and mode will indicate skewness. In a symmetrical distribution, they will all be equal.