What is the length of s=8.57, n=300, confidence level=95%

The length of the interval is of 1.8672.

Step-by-step explanation:

Length of a confidence interval:

Margin of error multiplied by 2.

Confidence interval:

We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Z-table as such z has a p-value of .

That is z with a pvalue of , so Z = 1.96.

Now, find the margin of error M as such

In which is the standard deviation of the population and n is the size of the sample.

s=8.57, n=300

Margin of error:

Length:

2*0.9336 = 1.8672

The length of the interval is of 1.8672.

answer: 180

step-by-step explanation:

12-2=10

20-2=18

18x10=180

c is the correct answer

step-by-step explanation: