A school football team scores 0, 1, 2, 4 and 8 goals in its five matches of a made-up season…

Step 1. The mean. $\dfrac{15}{5} = 3$ goals.

Step 2. The MAD. The distances from 3 are $3, 2, 1, 1, 5$, with total 12. MAD $= \dfrac{12}{5} = 2.4$ goals.

Step 3. Population SD. The squares are $9, 4, 1, 1, 25$, with total 40. $\sigma = \sqrt{\dfrac{40}{5}} = \sqrt{8} \approx 2.83$ goals.

Step 4. Sample SD. $s = \sqrt{\dfrac{40}{4}} = \sqrt{10} \approx 3.16$ goals.