Respuesta :

WojtekR
1. Mean.

[tex]\overline{x}=\dfrac{15+17+19+20+14+23+12}{7}=\dfrac{120}{7}\approx\boxed{17.14}[/tex]

2. Standard deviation.

First we have to square each value and calculate the mean of that squares:

[tex]\overline{x^2}=\dfrac{15^2+17^2+19^2+20^2+14^2+23^2+12^2}{7}=\boxed{\dfrac{2144}{7}}[/tex]

so the variance:

[tex]s^2=\overline{x^2}-\overline{x}^2=\dfrac{2144}{7}-\left(\dfrac{120}{7}\right)^2\approx\boxed{12.41}[/tex]

and the standard deviation:

[tex]s=\sqrt{s^2}=\sqrt{12.41}\approx\boxed{3.52} [/tex]

Otras preguntas