Concept explainers
If, as in Exercise 4.17, Y has density
find the mean and variance of Y.
4.17 The length of time required by students to complete a one-hour exam is a random variable with a density function given by
- a. Find c.
- b. Find F(y).
- c. Graph f(y) and F(y).
- d. Use F(y) in part (b) to lind F(–1), F(0), and F(1).
- e. Find the probability that a randomly selected student will finish in less than half an hour.
- f. Given that a particular student needs at least 15 minutes to complete the exam, find the probability that she will require at least 30 minutes to finish.
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Chapter 4 Solutions
Mathematical Statistics with Applications
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