University of California, Davis - Statistics

STA 103 MIDTERM I I page 22. The annual report is one of the most important documents produced by publicly ownedcompanies and is a document that incurs considerable expense in its production. However, moststockholders read the report only curiously, if at all. Suppose that 40% of stockholders read theircompany’s annual report and n = 10 stockholders of a publicly owned company randomlyselected from the firms registry of stockholders. Let X be the number of stockholders in thesample who read the annual report.(5)(a) Is X a discrete or continuous random variable? Write the probability function of X.(b) Find P[ X = 4 ]. Please write down the formula you use for calculating this probability.(10)(c) Find P[ X > 2 ].(12)(8)(d) Compute mean, variance and standard deviation of X.