Answer:
95% Confidence interval for the variance:
95% Confidence interval for the standard deviation:
Step-by-step explanation:
We have to calculate a 95% confidence interval for the standard deviation σ and the variance σ².
The sample, of size n=8, has a standard deviation of s=2.89 miles.
Then, the variance of the sample is
The confidence interval for the variance is:
The critical values for the Chi-square distribution for a 95% confidence (α=0.05) interval are:
Then, the confidence interval can be calculated as:
If we calculate the square root for each bound we will have the confidence interval for the standard deviation:
Answer:
Option A.
Step-by-step explanation:
we know that
The area of a trapezoid is equal to
we have
Convert feet to inches first
Remember that
so
substitute in the formula
396 divided by 3 is 132. 132 multiplied by 2 is 264. If you subtract 264 from 396, you end up with 132.
The amount of hamburgers sold on Thursday was 132.
.680 I think because 4 or less let it rest and 5 or more raise the score.