Assume the speed of vehicles along an open stretch of a certain highway in Texas that is not heavily traveled has an approximately Normal distribution with a mean of 71 mph and a standard deviation of 3.125 mph.

MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
icon
Related questions
Question
100%

Please answer question 1, section d.

Thanks

**Educational Website Content: Analyzing Vehicle Speeds and IQ Distributions**

---

### Problem 1: Vehicle Speeds on a Texas Highway

1. Assume the speed of vehicles along an open stretch of a certain highway in Texas, which is not heavily traveled, follows an approximately Normal distribution with a mean (μ) of 71 mph and a standard deviation (σ) of 3.125 mph.

(Make sure to show how you got your answers)

**Questions:**

a) **Current Speed Limit**: The current posted speed limit is 65 mph. What is the proportion of vehicles going above this limit?

b) **Below 50 mph**: What proportion of the vehicles would be going less than 50 mph?

c) **Between 60 and 75 mph**: What proportion of the vehicles would be going between 60 and 75 mph?

d) **New Speed Limit Proposal**: State authorities acknowledge that the road is not heavily trafficked and can handle a higher speed limit. However, they will implement a high fee for speeding over the new speed limit to ensure safety. Assume the same Normal distribution of speeds continues into the future. What should be the new speed limit so that only about 10% of vehicles exceed this limit? Show all of your reasoning and work in answering this.

---

### Problem 2: IQ Scores Distribution

2. Assume that IQ scores follow a Normal distribution with a mean (μ) of 100 and a standard deviation (σ) of 16. Using our IQR rule for determining IQ score outliers, what IQ scores would establish the lower and upper fences for determining outliers?

(Make sure to show how you got your answers)

---

**Instructions for Educators**: Encourage students to demonstrate their understanding by using the properties of Normal distributions and the IQR method. Provide step-by-step solutions to ensure students grasp key concepts such as z-scores and the calculation of fences for identifying outliers.
Transcribed Image Text:**Educational Website Content: Analyzing Vehicle Speeds and IQ Distributions** --- ### Problem 1: Vehicle Speeds on a Texas Highway 1. Assume the speed of vehicles along an open stretch of a certain highway in Texas, which is not heavily traveled, follows an approximately Normal distribution with a mean (μ) of 71 mph and a standard deviation (σ) of 3.125 mph. (Make sure to show how you got your answers) **Questions:** a) **Current Speed Limit**: The current posted speed limit is 65 mph. What is the proportion of vehicles going above this limit? b) **Below 50 mph**: What proportion of the vehicles would be going less than 50 mph? c) **Between 60 and 75 mph**: What proportion of the vehicles would be going between 60 and 75 mph? d) **New Speed Limit Proposal**: State authorities acknowledge that the road is not heavily trafficked and can handle a higher speed limit. However, they will implement a high fee for speeding over the new speed limit to ensure safety. Assume the same Normal distribution of speeds continues into the future. What should be the new speed limit so that only about 10% of vehicles exceed this limit? Show all of your reasoning and work in answering this. --- ### Problem 2: IQ Scores Distribution 2. Assume that IQ scores follow a Normal distribution with a mean (μ) of 100 and a standard deviation (σ) of 16. Using our IQR rule for determining IQ score outliers, what IQ scores would establish the lower and upper fences for determining outliers? (Make sure to show how you got your answers) --- **Instructions for Educators**: Encourage students to demonstrate their understanding by using the properties of Normal distributions and the IQR method. Provide step-by-step solutions to ensure students grasp key concepts such as z-scores and the calculation of fences for identifying outliers.
Expert Solution
Step 1

It is given that mean is 71 and standard deviation is 3.125.

trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps with 1 images

Blurred answer
Knowledge Booster
Frequency Statistics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.
Recommended textbooks for you
MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc
Probability and Statistics for Engineering and th…
Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning
Statistics for The Behavioral Sciences (MindTap C…
Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning
Elementary Statistics: Picturing the World (7th E…
Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON
The Basic Practice of Statistics
The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman
Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman