2B. (a) An exponential distribution has probability density function S (x) = -e¯z/a, x 2 0. %3D Show that the mean of the distribution is a and the variance is a². (b) A machine contains two belt drives, of different lengths. These have times to failure which are exponentially distributed, with mean times a and 2a. The machine will stop if either belt fails, and the failures of the belts are independent. Show that the chance that the machine is still operating after a time a from the start is e 32.
2B. (a) An exponential distribution has probability density function S (x) = -e¯z/a, x 2 0. %3D Show that the mean of the distribution is a and the variance is a². (b) A machine contains two belt drives, of different lengths. These have times to failure which are exponentially distributed, with mean times a and 2a. The machine will stop if either belt fails, and the failures of the belts are independent. Show that the chance that the machine is still operating after a time a from the start is e 32.
A First Course in Probability (10th Edition)
10th Edition
ISBN:9780134753119
Author:Sheldon Ross
Publisher:Sheldon Ross
Chapter1: Combinatorial Analysis
Section: Chapter Questions
Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...
Related questions
Question
Statistics and Probability
![2B.
(a) An exponential distribution has probability density function
ƒ (x) =
x 2 0.
Show that the mean of the distribution is a and the variance is a².
(b) A machine contains two belt drives, of different lengths. These have times to failure which
are exponentially distributed, with mean times a and 2a. The machine will stop if either belt
fails, and the failures of the belts are independent. Show that the chance that the machine is
still operating after a time a from the start is e 32.](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F25bf4691-7e3a-4c14-be0e-69758f750a69%2Fb7507dab-286f-40f3-bb55-9d759a946862%2F62g7zam_processed.jpeg&w=3840&q=75)
Transcribed Image Text:2B.
(a) An exponential distribution has probability density function
ƒ (x) =
x 2 0.
Show that the mean of the distribution is a and the variance is a².
(b) A machine contains two belt drives, of different lengths. These have times to failure which
are exponentially distributed, with mean times a and 2a. The machine will stop if either belt
fails, and the failures of the belts are independent. Show that the chance that the machine is
still operating after a time a from the start is e 32.
Expert Solution
![](/static/compass_v2/shared-icons/check-mark.png)
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 3 steps
![Blurred answer](/static/compass_v2/solution-images/blurred-answer.jpg)
Recommended textbooks for you
![A First Course in Probability (10th Edition)](https://www.bartleby.com/isbn_cover_images/9780134753119/9780134753119_smallCoverImage.gif)
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON
![A First Course in Probability](https://www.bartleby.com/isbn_cover_images/9780321794772/9780321794772_smallCoverImage.gif)
![A First Course in Probability (10th Edition)](https://www.bartleby.com/isbn_cover_images/9780134753119/9780134753119_smallCoverImage.gif)
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON
![A First Course in Probability](https://www.bartleby.com/isbn_cover_images/9780321794772/9780321794772_smallCoverImage.gif)