Let X and Y be independent random variables representing the lifetime (in one billion years) of TypeA and Type B stars, respectively. Both variables have exponential distributions, and the mean of X is3 and the mean of Y is 11. What is the variance of the total lifetime of three times a Type A star anda Type B star?

Given data is mean of X is 3mean of Y is 11we have to find the variance of the total life time of 3…

Answered: Let X and Y be independent random…

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...

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What is the Discrete Variable Variance for the following numbers:x = 0 and P(X = x) = 0.19x = 1 and P(X = x) = 0.27x = 2 and P(X = x) = 0.21x = 3 and P(X = x) = 0.33
Suppose you would like to keep a test tube at 48F (exactly), but your refrigeration unit exhibits some random fluctuations, so that the difference between the temperature at which you set the thermostat and the true temperature is distributed normally with mean 0 and variance 1.96. What is the highest you can set the thermostat and be 95% sure that the true temperature is no more than 48F?
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