Question
Three students answer a true-false question on a test randomly. A random variable x represents the...
Three students answer a true-false question on a test randomly. A random variable x represents the number of answers of true among the three students, taking on the value 0, 1, 2, or 3.
(a) Find the frequency distribution for x.
(b) Find the probability distribution for x.
For the same random variable x as the previous problem, find the following:
(a) The expected value (b) The variance (c) The standard deviation
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