SOLUTION: A box contains 4 white shirts and 3 blue shirts. Two shirts are picked at random from the box, one at a time without replacement. What is the probability that the first chip is whi

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Question 1202367: A box contains 4 white shirts and 3 blue shirts. Two shirts are picked at random from the box, one at a time without replacement. What is the probability that the first chip is white and the second chip is blue?
Found 2 solutions by greenestamps, ikleyn:
Answer by greenestamps(13200) About Me  (Show Source):
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First shirt (not chip) white: There are 7 shirts, of which 4 are white. The probability is 4/7.

Second shirt (not chip) blue: There are 6 shirts left of which 3 are blue. The probability is 3/6 = 1/2.

By the fundamental counting principle, the probability of white first and then blue second is the product of those two probabilities.

ANSWER: (4/7)(1/2) = 2/7

Answer by ikleyn(52785) About Me  (Show Source):
You can put this solution on YOUR website!
.

The probability is

    P = %284%2F7%29%2A%283%2F6%29 = reduce fractions = %284%2F7%29%2A%281%2F2%29 = reduce fractions again = 2%2F7.    ANSWER


First factor  4%2F7  is the probability to pick randomly one of 4 white shirts from the original total  4+3 = 7  shirts.


Second factor  3%2F6%29  is the probability to pick randomly one of 3 blue shirts from the remaining  7-1 = 6  shirts.

Solved, with explanations.