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A bowl contains 3 red, 8 blue, and 7 black beads. Margaret randomly selects 3 beads one after the other without replacement. Find the probability of getting a red, blue, and black bead, in that order.

1 Answer

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Since your second pick is affected by your first pick & your third pick is affected by the first two, it is dependent.

First pick: 18 marbles, 3 are red, so odds are 3/18 = 1/6

Second pick: 17 marbles, 8 are blue, odds are 8/17

Third pick: 16 marbles, 7 are black, odds are 7/16

1/6 * 8/17 * 7/16 = 56/1632 = 7/204 & as mentioned before it's dependent
User Nigel Small
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