What is the written form of 30.55

Which of the following best describes the set of numbers shown below?

Vsevolod [243]

Answer:

spongebob at the bottom of the sea

Step-by-step explanation:

In a plain, robust, conversational style, the author known as “Elena Ferrante” has captivated readers worldwide with her chronicle of a complicated friendship between two women.

5 0

3 years ago

Find the 95% confidence intervalfor the variance and standard deviation for the time ittakes a customer to place a telephone ord

Aliun [14]

Answer:

$8.637 \leq \sigma^2 \leq 28.93$

$2.939 \leq \sigma \leq 5.379$

Step-by-step explanation:

Data given and notation

s represent the sample standard deviation

$\bar x$ represent the sample mean

n=23 the sample size

Confidence=95% or 0.95

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population mean or variance lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

The Chi Square distribution is the distribution of the sum of squared standard normal deviates .

Calculating the confidence interval

The confidence interval for the population variance is given by the following formula:

$\frac{(n-1)s^2}{\chi^2_{\alpha/2}} \leq \sigma \leq \frac{(n-1)s^2}{\chi^2_{1-\alpha/2}}$

The sample standard deviation for this case was s = 3.8

The next step would be calculate the critical values. First we need to calculate the degrees of freedom given by:

$df=n-1=23-1 =22$

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a tabele to find the critical values.