A box contains 3 red and 4 green marbles. Five marbles are drawn without replacement. Let...

Question

Question

A box contains 3 red and 4 green marbles. Five marbles are drawn without replacement. Let X denote the number of red marbles obtained.

a) Construct the probability distribution of X.

b) What is the expected number of red marbles?

Answer 1

Answer #1

a)

X P(X)

1 0.143

2 0.571

3 0.286

b) Expected number of red marbles = n * k/N = 5 * 3/7 = 2.143

Answer 2

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