Assume the random variable X is normally distributed, with mean p= 44 and standard deviation o = 9. Find the 13th percentile.
Assume the random variable X is normally distributed, with mean p= 44 and standard deviation o = 9. Find the 13th percentile.
MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
Related questions
Question
![**Understanding Percentiles in a Normal Distribution**
Consider the random variable \( X \), which is normally distributed with a mean (\( \mu \)) of 44 and a standard deviation (\( \sigma \)) of 9. Our goal is to find the 13th percentile of this distribution.
### Key Concepts:
- **Normal Distribution**: A probability distribution that is symmetric about the mean, depicting that data near the mean are more frequent in occurrence than data far from the mean.
- **Mean (\( \mu \))**: The average or central value.
- **Standard Deviation (\( \sigma \))**: A measure of the amount of variation or dispersion in a set of values.
- **Percentile**: A measure used in statistics to indicate the value below which a given percentage of observations in a group falls.
### Problem Statement:
Assume the random variable \( X \) is normally distributed, with mean \( \mu = 44 \) and standard deviation \( \sigma = 9 \). Find the 13th percentile.
### Calculate the 13th Percentile:
The 13th percentile means that 13% of the data falls below this value. To find this value, you can use statistical tables or software that provides the cumulative distribution function (CDF) of the normal distribution.
1. **Z-Score Approach:**
- A Z-score is a measure of how many standard deviations an element is from the mean.
- Use the standard normal distribution table to find the Z-score corresponding to a cumulative probability of 0.13.
- Convert the Z-score to the corresponding \( X \) value using the formula:
\[
X = \mu + Z \times \sigma
\]
2. **Using Statistical Software or Tools:**
- Input the mean, standard deviation, and desired percentile to obtain the result directly.
By following such methods, you can determine the precise value at the 13th percentile for the given normal distribution.](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2Ffb1fb1b3-bc63-4148-8150-b8fd23758433%2Fc8c9912a-c86e-465e-93cb-08550a71224d%2F9rfcuhg_processed.jpeg&w=3840&q=75)
Transcribed Image Text:**Understanding Percentiles in a Normal Distribution**
Consider the random variable \( X \), which is normally distributed with a mean (\( \mu \)) of 44 and a standard deviation (\( \sigma \)) of 9. Our goal is to find the 13th percentile of this distribution.
### Key Concepts:
- **Normal Distribution**: A probability distribution that is symmetric about the mean, depicting that data near the mean are more frequent in occurrence than data far from the mean.
- **Mean (\( \mu \))**: The average or central value.
- **Standard Deviation (\( \sigma \))**: A measure of the amount of variation or dispersion in a set of values.
- **Percentile**: A measure used in statistics to indicate the value below which a given percentage of observations in a group falls.
### Problem Statement:
Assume the random variable \( X \) is normally distributed, with mean \( \mu = 44 \) and standard deviation \( \sigma = 9 \). Find the 13th percentile.
### Calculate the 13th Percentile:
The 13th percentile means that 13% of the data falls below this value. To find this value, you can use statistical tables or software that provides the cumulative distribution function (CDF) of the normal distribution.
1. **Z-Score Approach:**
- A Z-score is a measure of how many standard deviations an element is from the mean.
- Use the standard normal distribution table to find the Z-score corresponding to a cumulative probability of 0.13.
- Convert the Z-score to the corresponding \( X \) value using the formula:
\[
X = \mu + Z \times \sigma
\]
2. **Using Statistical Software or Tools:**
- Input the mean, standard deviation, and desired percentile to obtain the result directly.
By following such methods, you can determine the precise value at the 13th percentile for the given normal distribution.
Expert Solution

This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 1 images

Knowledge Booster
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
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc

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
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning

MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc

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
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning

Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON

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
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman