Suppose the mean grade for a statistics midterm exam was 75, with a standard deviation of 10. Assume that your grades were normally distributed. [ 40 pts. Total]
a. What percentage of students received at least an 90? [7.5 pts]
b. What percentage of students received an 84? [5 pts.]
c. What percentage of students received a grade between 60 and 79? [10 pts.]
d. What percentage of students received a grade less than 70? [7.5 pts.]
e. If 2 students failed the exam, i.e. their grades were less than 60, how many students took the test? Hint: First focus on p(x<60). [10 pts.]
DO NOT SHOW WORK IN THE SPACE BELOW. You must attach a document to question 6 showing your work for problems 3-5 in order to receive credit. All files must be pdf format. You will receive a 0 grade for a question if you do not show work or give an explanation for your answer (graphs preferred).
Suppose the mean grade for a statistics midterm exam was 75, with a standard deviation of...
THINKING/COMMUNICATION 7. A post-secondary class has 600 students. The mean grade on their midterm exam is 70%, with a standard deviation of 15. a. Find the Z-score of a student who scored 80% on his exam. [2 marks] b. Find the percentage of students who failed the exam. [3 marks] c. How many students failed the exam (i.e. scored less than 49%)? [1 mark] d. Your friend claims he scored in the 99th percentile on his exam. What mark must...
The results from a statistics class' first exam are as follows: The mean grade obtained by its 25 students is 83, with a standard deviation of 11. The distribution of grades was unimodal and symmetrical. What is the probability that a student received a grade above 90? The results from a statistics class' first exam are as follows: The mean grade obtained by its 25 students is 83, with a variance of 121. The distribution of grades was unimodal and symmetrical....
In a statistics class, the average grade on the final examination was 75 with a standard deviation of 5. a. At least what percentage of the students received grades between 50 and 100? Determine an interval for the grades that will be true for at least 70% of the students. b.
if statistics test scores were normally distributed with a mean of 81 and a standard deviation of 4, a) what is the probability that a randomly selected student scored less than 70? b) what percentage of students had a B on the exam? c) the top 10% of the class had what grades?
Grades on a biology exam are approximately normally distributed with a mean of 78 and a standard deviation of 8. Originally Dr. Smith decides to curve course grades as follows: Students who score above the 90 percentile will receive an A Students whose scores are in the 80-89.percentiles receive a B Students whose scores are in the 70th-795h percentiles receive a C Students whose scores are in the 60-69 percentiles receive a D Students who score below the 60th percentile...
The scores on a psychology exam were normally distributed with mean of 55 and a standard deviation of 5. A failing grade on the exam was anything 2 or more standard deviations below the mean. What was the cutoff for a failing score? Approximately what percentage of the students failed? The cutoff for a failing score was 45. (Simplify your answer.) Approximately percent of the students failed. (Round to one decimal place as needed.)
Suppose time taken to grade an exam-paper by an examiner has mean 12.8 min. and standard deviation 5 min. If the examiner has to grade 46 exam-papers, what is the approximate probability that she will finish grading in less than 609 min. (assuming grading times are independent and she grades continuously)? Answer to 4 decimal place
A student's course grade is based on one midterm that counts as 10% of his final grade, one class project that counts as 10% of his final grade, a set of homework assignments that counts as 35% of his final grade, and a final exam that counts as 4545% of his final grade. His midterm score is 65 his project score is 92 his homework score is 89 and his final exam score is 60. What is his overall final...
Student stress at final exam time comes partly from the
uncertainty of grades and the consequences of those grades. Can
knowledge of a midterm grade be used to predict a final exam grade?
A random sample of 200 BCOM students from recent years was taken
and their percentage grades on assignments, midterm exam, and final
exam were recorded. Let’s examine the ability of midterm and
assignment grades to predict final exam grades.
The data are shown here:
Assignment
Midterm
FinalExam...
A student's course grade is based on one midterm that counts as 20% of his final grade, one class project that counts as 25% of his final grade, a set of homework assignments that counts as 45% of his final grade, and a final exam that counts as 10% of his final grade. His midterm score is 60, his project score is 90, his homework score is 92, and his final exam score is 78. What is his overall final...