Descriptive Statistics

Mean

Find the mean (average) of a data set by summing all values and dividing by the count.

Example

Add the data values and divide by the count.

highlighted = computed this step

Step 1 — Data

List the data values.

posx14283641057\begin{array}{cc}\text{pos} & \text{x} \\ 1 & 4 \\ 2 & 8 \\ 3 & 6 \\ 4 & 10 \\ 5 & 7\end{array}
Data values4x18x26x310x47x5

Step 2 — Sum

Add all data values.

S=4+8+6+10+7=35S= 4 + 8 + 6 + 10 + 7 = \hl{35}
total = 354x18x26x310x47x5

Step 3 — Divide by count

Divide the sum by the count.

xˉ=35/5=7\bar{x}= 35 / 5 = \hl{7}
35 shared across 5 values gives 74x18x26x310x47x57

Step 4 — Result

State the mean.

xˉ=7\bar{x}= \hl{7}
mean = 74x18x26x310x47x57
mean The mean of a data set {x₁, x₂, …, xₙ} is: mean = (x₁ + x₂ + ⋯ + xₙ) / n