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Problem 1

During the first year at a university that uses a 4 -point grading system, a freshman took ten 3 -credit courses and received two As, three Bs, four Cs, and one D. a. Compute this student's grade-point average. b. Let the random variable \(X\) denote the number of points corresponding to a given letter grade. Find the probability distribution of the random variable \(X\) and compute \(E(X)\), the expected value of \(X\).

Expert verified

a. The student's grade-point average is 2.6.
b. The probability distribution of the random variable X is:
P(X=1) = 1/10, P(X=2) = 4/10,
P(X=3) = 3/10, P(X=4) = 2/10,
and the expected value of X is 2.6.

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