SOLUTION: A box contains ten marbles,seven of which are black and three are red.three marbles are drawn one after the other without replacement. Find the probability of choosing A. At least

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Question 907586: A box contains ten marbles,seven of which are black and three are red.three marbles are drawn one after the other without replacement. Find the probability of choosing
A. At least two black marbles
B. At most two black marbles
Answer by reviewermath(1029) About Me  (Show Source):
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A box contains ten marbles,seven of which are black and three are red.three marbles are drawn one after the other without replacement. Find the probability of choosing
A. At least two black marbles
P(X ≥ 2) = 1 - P(X = 0) - P(X = 1)
= 1 - -
= highlight%2849%2F60%29 or highlight%280.8167%29 (4 decimal places)
B. At most two black marbles
P(X ≤ 2) = P(X = 0) + P(X = 1) + P(X = 2)
= + +
= highlight%2817%2F24%29 or highlight%280.7083%29 (4 decimal places)