STATISTC 515 Final: STATS 515 UMass Amherst S515.Fall15.Final
Document Summary
Instructions: the total score is 100 points, there are six questions, show all your work, some questions have more than one parts. April 6, 2010: let the cumulative distribution function(c. d. f. ) of a continuous random variable y be (7points) (a) Find the probability density function(p. d. f) of y , f (y). 0 y < 4, y 4. (7points) (b) Find the expected value of y , e(y ). (3points) (c) Find p (1. 5 y 3). (3points) (d) Find p (y 1. 5 | y 3). April 6, 2010: a candy maker produces mints that have a label weight of 20. 4 grams. Assume that the weights of these mints have a normal distribution with mean 21. 37 and variance 0. 16 (i. e. , the weights of these mints n (21. 37, 0. 16)). Let y denote the weight of a single mint selected at random from the production line. What is the probability that y is larger or equal to 22. 07? (5points) (b)
