ShmoopTube

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You can't handle the Shmoop!

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Twelve cards are placed in a deck.

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This kind of deck. Get that ship out of here.

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Three of these cards are blue, four are green, and five are red.

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If Silas draws one card, then places it in his pocket and draws another,

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what is the probability that both cards will be blue?

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Round to the nearest tenth of a percent. And here are the potential answers…

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Remember that the probability of a single trial is:

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favorable divided by number of possible outcomes.

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In the first trial, out of 12 cards, there are 3 blue cards.

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There are 3 favorable outcomes, and 12 possible. This comes out to 3/12 or 1/4, or 25% chance.

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Next, if we picked a blue card the first time, there would be 2 blue cards left in the deck,

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and only 11 in total...

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…which comes out to about 18%. To find the combined probability, we simply

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multiply the two probabilities together.

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.25 times .18 is .045…or 4.5%.

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So our answer is (A).

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