Question

Complete the chart to find the mean, variance, and standard deviation. Remember to use commas and round numbers to the nearest tenth. Need help

Answer 1

Answer: The mean of the data is 433.75, variance of the data is 99667.19 and the standard deviation of the data is 315.7011.

Explanation:

The given data is 900, 35, 500 and 300.

The number of observation is 4.

Formula of mean is,

$\text{Mean}=\frac{\text{Sum of observations}}{\text{Number of observations}}$

$\bar{X}=\frac{900+35+50+300}{4} =433.75$

The formula of variance is given below,

$\sigma^2=\frac{1}{n}\sum{(X-\bar{X})^2}$

$\sigma^2=\frac{398668.75}{4}$

$\sigma^2=99667.19$

The variance of the data is 99667.19

$\sigma=\sqrt{99667.19}$

$\sigma=315.7011$

The standard deviation of the data is 315.7011.

The other information or values of given chart is shown in the attached table.

Answer 2

Answer:

i.  mean of the data is 402.5

ii.  variance of the data is 77556.25

iii.  standard deviation of the data is 278.49

Step-by-step explanation: (x - ⁻x)²

from the chart given to me, the observation are:  45, 340, 400, 825

i.  mean is the summation of the observation divided by number of observation. ∈x÷n =( 45 + 340 + 400 + 825)÷ 4 = 402.5

ii.  variance is the square of the difference between the observation and mean divided by the number of observation.

variance = (45-402.5)²+(340-402.5)²+(400-402.5)²+(825-402.5)²÷4=77556.5