Question
In: Statistics and Probability
Descriptive analysis revealed that the mean Test 3 score of all 63 students in Dr. Bills’s...
Descriptive analysis revealed that the mean Test 3 score of all 63 students in Dr. Bills’s statistics courses was an 80. Similarly, the standard deviation for all students’ Test 3 scores was found to be 16. Assume the Test 3 scores are approximately normally distributed.
5. Determine the Test 3 score that corresponds to a z-score of -2.18. Round your solution to the nearest whole number.
6. Find the 75th percentile. That is, find the test score such that 75% of all test scores are below it. Hint: See example on the Chapter 6 handout. Round your solution to the nearest whole number.
Solutions
Expert Solution
Mean = 
= 80
standard deviation = 
= 16
Sample size = n = 63
5. Determine the Test 3 score that corresponds to a z-score of -2.18. Round your solution to the nearest whole number.
z = -2.18
6. Find the 75th percentile. That is, find the test score such that 75% of all test scores are below it.
We need to find 
such that
We know that
orchestra answered 1 year agoRelated Solutions
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