The data below show a sample of grades of students on their final exam in a statistics class. Grades 81 84 83 69 80 70 74 67 71 64 63 68 79 a) Find the average final exam grades for this class. [Round your answer to two decimal places.] The mean of midterm exam for the class was 83.31. Did the students tend to perform better on their final exam or midterm exam? Select an answer Final Exam Midterm Exam b) Find the sample standard deviation of the final exam grades. [Round your answer to two decimal places.] The standard deviation of the midterm grades was 5.31. Did the student's final grades tend to have more or less variation than their midterm grades? Select an answer more variation less variation
Inverse Normal Distribution
The method used for finding the corresponding z-critical value in a normal distribution using the known probability is said to be an inverse normal distribution. The inverse normal distribution is a continuous probability distribution with a family of two parameters.
Mean, Median, Mode
It is a descriptive summary of a data set. It can be defined by using some of the measures. The central tendencies do not provide information regarding individual data from the dataset. However, they give a summary of the data set. The central tendency or measure of central tendency is a central or typical value for a probability distribution.
Z-Scores
A z-score is a unit of measurement used in statistics to describe the position of a raw score in terms of its distance from the mean, measured with reference to standard deviation from the mean. Z-scores are useful in statistics because they allow comparison between two scores that belong to different normal distributions.
The data below show a sample of grades of students on their final exam in a statistics class.
| Grades |
|---|
| 81 |
| 84 |
| 83 |
| 69 |
| 80 |
| 70 |
| 74 |
| 67 |
| 71 |
| 64 |
| 63 |
| 68 |
| 79 |
a) Find the average final exam grades for this class. [Round your answer to two decimal places.]
The mean of midterm exam for the class was 83.31. Did the students tend to perform better on their final exam or midterm exam? Select an answer Final Exam Midterm Exam
b) Find the sample standard deviation of the final exam grades. [Round your answer to two decimal places.]
The standard deviation of the midterm grades was 5.31. Did the student's final grades tend to have more or less variation than their midterm grades? Select an answer more variation less variation
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