Math Problem Solving statistics and probability

Question

asked Mar 28, 2022 35.4k views

1 Answer

Duckboycool · Answer 1 · 2022-04-03T17:33:52+0000

Answer:

Standard Deviation = 3.22

Variance = 10.36

Explanation:

x P(x) x × P(x) x² x² × P(x)

19 0.20 3.8 361 72.2

10 0.20 2 100 20

11 0.30 3.3 121 36.3

12 0.20 2.4 144 28.8

13 0.10 1.3 169 16.9

____________________________________________

12.8 174.2 => Total

Mean Formula

$\mu_x = \sum(x * P(x))$
= 12.8

$\mu_x^2 = 163.84$

Variance Formula

$\sigma _x^2 = \sum[x^2 * P(x)] - \mu_x^2$

$= 174.2- 163.84\\\\=10.36$

Standard Deviation Formula

$Standard\ deviation, \ \sigma_x = √(Variance)$

$=√(10.36)\\\\=3.218$