Question 35 (1 point) When the test scores of 500 students were analyzed, a mean score of 82 was obtained with a standard deviation of 8. Assuming that the scores were normally distributed, how many students had scores between 74 and 90? 68% 340 475 95% 99.7%
Added by Belen M.
Close
Step 1
The z-score is a measure of how many standard deviations an element is from the mean. Z = (X - μ) / σ For X = 74, Z1 = (74 - 82) / 8 = -1 For X = 90, Z2 = (90 - 82) / 8 = 1 Now, we know that in a normal distribution: Show more…
Show all steps
Your feedback will help us improve your experience
Adi S and 93 other Intro Stats / AP Statistics educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
A set of 700 exam scores is normally distributed with a mean = 78 and standard deviation = 5. How many students scored higher than 78? How many students scored between 73 and 83? How many students scored between 68 and 88? How many students scored between 78 and 83? How many students scored lower than 73? How many students scored lower than 83?
Adi S.
Grades are normally distributed with a mean of 75 and a standard deviation of 8. Calculate the Z score of a student who got an 81. Z =
Anna D.
On the final examination, the mean was 72 and the standard deviation was 15. 1) Determine the standard scores (z-values) of students receiving the grade of 65. 2) Students receiving the grade of 85. 3) Probability that a student will score greater than 75. 4) Probability that a student will score lower than 65. 5) Find the corresponding standard score of -0.50 and the corresponding score of 1.
Suman K.
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
Watch the video solution with this free unlock.
EMAIL
PASSWORD