Answer:
Step-by-step explanation:
We want to determine a 95% confidence interval for the mean mean test score of students.
Number of sample, n = 25
Mean, u = 81.5
Standard deviation, s = 10.2
For a confidence level of 95%, the corresponding z value is 1.96. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean ± z score ×standard deviation/√n
It becomes
81.5 ± 1.96 × 10.2/√25
= 81.5 ± 1.96/× 2.04
= 81.5 ± 3.9984
The lower end of the confidence interval is 81.5 - 3.9984 =77.5
The upper end of the confidence interval is 81.5 + 3.9984 = 85.5
Therefore, with 95% confidence interval, the mean test score of students is between 77.5 and 85.5
I believe the length of the fence is 640. (Don't count on my answer, it may not be right).
Answer:
i think c but im not positive
Step-by-step explanation:
Answer:
John needs
yards of blue ribbon.
Step-by-step explanation:
We have been given that Jon uses a piece of red ribbon witch is 3/4th yard long. Jon also needs blue ribbon that is 5 times as long as the ribbon. We are asked to find the amount of blue ribbon that John needs.
To find the amount of blue ribbon that John needs, we will multiply amount of red ribbon by 5 as shown below:




Therefore, John needs
yards of blue ribbon.
The slope of a line is the amount of units it goes across the x axis by how many units it goes up the y axis. A line with slope 3 goes 3 spaces up for every one space along.