In a statistics class, the average grade on the final examination was 75 with a standard...
In a chemistry class, the average grade on the final examination was 60 with a standard deviation of 4. Use Chebyshev's theorem to answer the following questions. a. At least what percentage of students received grades between 54 to 66? b. At least what percentage of students received grades between 52 to 68 hours? C. Determine an interval for the grades that will be true for at least 80% of the students. (Hint: First compute the Z-score.)
The final exam grade of a statistics class has a skewed distribution with mean of 76 and standard deviation of 7.4. If a random sample of 36 students selected from this class, then what is the probability that the average final exam grade of this sample is between 75 and 80? Answer: (keep 4 decimal places)
A student believes that the average grade on the statistics final examination was 87. A sample of 36 final examinations was taken. The average grade in the sample was 83.96 with a standard deviation of 12. The student wants to test whether the average is different from 87 at 90% level of confidence. Compute the p-value for this test. NOTE: WRITE YOUR ANSWER WITH 4 DECIMAL DIGITS. DO NOT ROUND UP OR DOWN.
Fifty students are enrolled in an Economics class. After the first examination, a random sample of five papers was selected. The grades were 60, 70, 75, 80, 90. a. Calculate the estimate of the standard error of the mean. b. What assumption must be made before we can determine an interval for the mean grade of all the students in the class? Explain why? c. Assume the assumption of part(b) is met. Provide a 90% confidence interval for the mean...
Dr. B computed descriptive statistics for final grades in her PSY 210 classes at the end of the semester with the following results: min = 52 max = 99 mean = 83 median = 87 standard deviation = 13 If you provided only these descriptive statistics and the fact that grades were normally distributed (no raw data) to someone interested in your findings, what would they be able to conclude about the range of most (roughly 68%) of scores in...
A set of final examination grades in an introductory statistics course is normally distributed, with a mean of 78 and a standard deviation of 8. What is the probability that a student scored between 70 and 99? The probability that a student scored between 70 and 99 is =?
Scores on Professor Combs Statistics Final Exams have a long term history of being normally distributed with a mean of μ=70 and a standard deviation of σ=8 a.) Find the probability that a single student will score above a 75 on the Final exam. b.) Find the probability that a single student will score between a 65 and 75 on the Final exam. c.) Find the probability that an entire class of 20 students will have a class average above a 75 on...
A student believes that the average grade on the statistics final examination is 87. A sample of 36 final examinations is taken. The average grade in the sample is 83.96. The population variance is 144. Compute the probability of a Type Il error if the average grade on the final is 85,
examination grades in an introductory statistics course is normally distributed, with a mean of 75 and a standard deviation of 7. Complete parts (a) through (d) a. What is the probablity that a student scored below 87 on this exam? The probability that a shudent scored below 87 is (Round to four decimal places as needed.) b What is the probability that a student scored between 68 and 94 The probability that a student soored between 68 and 94 is...
A set of final examination grades in an introductory statistics course is normally distributed, with a mean of 73 and a standard deviation of 7. Complete parts (a) through (d). a. What is the probability that a student scored below 86 on this exam? (Round to four decimal places as needed.) b. What is the probability that a student scored between 66 and 93? (Round to four decimal places as needed.) c. The probability is 55% that a student taking...