Question 3 The price-earnings (PE) ratios of a sample of stocks have a mean value of 13.25 and a standard deviation of 1.2. If the PE ratios have a bell-shaped distribution, use the 68-95-99.7 Rule to estimate the percentage of PE ratios that fall between: a. 10.85 and 15.65 b. 9.65 and 16.85 Question 4 Scores on a certain intelligence test for children between ages 13 and 15 years are approximately normally distributed with µ=106 and sigma =15. Provide your solutions rounded to 3 decimal digits. a. What proportion of children aged 13 to 15 years old have scores on this test above 96? b. Enter the score which marks the lowest 20 percent of the distribution. c. Enter the score which marks the highest 15 percent of the distribution.
Added by Nicholas H.
Step 1
25 and the standard deviation is 1.2, we can use the 68-95-99.7 Rule to estimate the percentage of PE ratios that fall between 10.85 and 15.65. 10.85 is 2 standard deviations below the mean (13.25 - 2*1.2) and 15.65 is 1.33 standard deviations above the mean (13.25 Show more…
Show all steps
Close
Your feedback will help us improve your experience
David Nguyen and 89 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
Question 11 The distribution of the amount of money spent by students on textbooks in a semester is approximately normal in shape with a mean of 381 and a standard deviation of 23. According to the standard deviation rule, approximately 95% of the students spent between $ and $ on textbooks in a semester. Question 12 The distribution of IQ (Intelligence Quotient) is approximately normal in shape with a mean of 100 and a standard deviation of 20. According to the standard deviation rule, % of people have an IQ between 80 and 120. Do not round. Question 13
David N.
Scores on a certain intelligence test for children between ages 13 and 15 years are approximately normally distributed with mu = 96 and sigma = 18. (a) What proportion of children aged 13 to 15 years old have scores on this test above 86 ? (NOTE: Please enter your answer in decimal form. For example, 45.23% should be entered as 0.4523.) Answer: (b) Enter the score which marks the lowest 30 percent of the distribution. Answer: (c) Enter the score which marks the highest 15 percent of the distribution. Answer:
Supreeta N.
Scores on a certain intelligence test for children between ages 13 and 15 years are approximately normally distributed with mean 101 and standard deviation 18 (a) What proportion of children aged 13 to 15 years old have scores on this test above 96 ? (NOTE: Please enter your answer in decimal form. For example, 45.23% should be entered as 0.4523.) Answer: (b) Enter the score which marks the lowest 20 percent of the distribution. Answer: (c) Enter the score which marks the highest 15 percent of the distribution. Answer:
Lynn L.
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD