Lucille, Rocio, and Cristina are all taking College Mathematics but from different professors. They all recently took a statistics exam and the exam scores were normally distributed in each of their classes. Lucille's class had an average grade of 85 and the standard deviation was 3. Lucille earned 89.5 on the exam. Rocio's class had an average grade of 83 and the standard deviation was 4. Rocio earned 87.4 on the exam. Cristina's class had an average grade of 76 and the standard deviation was 6. Cristina earned 79.3 on the exam. Since some professors give harder exams than others, these students decided to use statistics to figure out who did the best on their exam.
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.
Lucille, Rocio, and Cristina are all taking College Mathematics but from different professors. They all recently took a statistics exam and the exam scores were
- Lucille's class had an average grade of 85 and the standard deviation was 3. Lucille earned 89.5 on the exam.
- Rocio's class had an average grade of 83 and the standard deviation was 4. Rocio earned 87.4 on the exam.
- Cristina's class had an average grade of 76 and the standard deviation was 6. Cristina earned 79.3 on the exam.
Since some professors give harder exams than others, these students decided to use statistics to figure out who did the best on their exam.
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