Question

In: Statistics and Probability

Suppose that the probability of obtaining a particular grade in an undergraduate statistics course, is defined...

Suppose that the probability of obtaining a particular grade in an undergraduate statistics course, is defined by the following table:

grade A B C D F
probability .25 .35 .2 .15 .05

(a) Using the usual numerical values for the grades, define the corresponding random variable, X, and its probability mass function, p(x).

(b) Calculate P(X ≤ 2), P(X < 2), and P(X ≥ 3).

(c) Plot the cumulative distribution function F(x).

(d) Compute the mean µ = E(X).

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Expert Solution

orchestra answered 2 years ago
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