Twenty-five identical looking packets of white powder are such that nineteen contain cocaine and six do not. Four packets were randomly selected, and the contents were tested and found to contain cocaine. Two additional packets were selected from the remainder and sold by undercover police officers to a single buyer. Use R to calculate the probability that the 6 packets randomly selected are such that the first 4 all contain cocaine and the 2 sold to the buyer do not. (Round your answer to three decimal places.
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Step 1: The probability that the first 4 packets selected contain cocaine is: $$P(4 \text{ cocaine}) = \frac{19}{25} \times \frac{18}{24} \times \frac{17}{23} \times \frac{16}{22}$$ Show more…
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Twenty identical looking packets of white power are such that 15 contain cocaine and 5 do not. Four packets were randomly selected, and the contents were tested and found to contain cocaine. Two additional packets were selected from the remainder and sold by undercover police officers to a single buyer. What is the probability that the 6 packets randomly selected are such that the first 4 all contain cocaine and the 2 sold to the buyer do not?
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