5. ISE has installed a new air purifying system in all 25 lecture rooms, one per room. Suppose 2 of them are defective. If the lifetime of a good air purifier is exponentially distributed with mean 5 years and only 1 year for a defective one. (a) Find the chance that one of the installed air purifiers lasts for more than 3 years. (b) If an installed air purifier has lasted for more than 3 years, find the probability that it will last for another 3 years. (c) Write the expression for the probability that at least 8 of the installed air purifiers last for more than 3 years, then estimate the value.
5. ISE has installed a new air purifying system in all 25 lecture rooms, one per room. Suppose 2 of them are defective. If the lifetime of a good air purifier is exponentially distributed with mean 5 years and only 1 year for a defective one. (a) Find the chance that one of the installed air purifiers lasts for more than 3 years. (b) If an installed air purifier has lasted for more than 3 years, find the probability that it will last for another 3 years. (c) Write the expression for the probability that at least 8 of the installed air purifiers last for more than 3 years, then estimate the value.
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
Hurry up
Expert Solution
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 4 steps
Recommended textbooks for you
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON