The probability that a person passes organic chemistry the first time he enrolls is .8 The probability that a person passes organic chemistry the second time he enrolls is .9 . \ \ \ \ a) Find the probability that a person fails the first time but passes the second time. \ \ \ \ B. Find the probability that a person fails both times.

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Step 1:

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The probability of the person passes the organic chemistry first time is $\"\"$ .

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The probability of the person passes the organic chemistry second time is $\"\"$ .

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The probability of the person fails first time is $\"\"$ .

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The probability of the person fails second time is $\"\"$ .

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$\"\"$

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(a)

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The probability that a person fails the first time but passes the second time is $\"\"$ .

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The events $\"\"$ and $\"\"$ are independent events, $\"\"$ .

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Substitute $\"\"$ and $\"\"$ .

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$\"\"$ .

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The probability that a person fails the first time but passes the second time is $\"\"$ .

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(b) The probability that a person fails both times is $\"\"$ .

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The events $\"\"$ and $\"\"$ are independent events, $\"\"$ .

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$\"\"$ .

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The probability that a person fails both times is $\"\"$ .

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