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An urn has 24 balls that are identical except that 8 are white, 7 are red, and 9 are blue. What is the probability that all are white if 3 are selected randomly without replacement?

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Final answer:

The probability of selecting 3 white balls consecutively from an urn of 24 balls, which contains 8 white balls, without replacement is 1/36.

Step-by-step explanation:

The student is asking for the probability of selecting 3 white balls from an urn with a total of 24 balls, where 8 are white, 7 are red, and 9 are blue, without replacement. The probability of choosing one white ball is initially the number of white balls divided by the total number of balls, which is 8/24. After choosing one white ball, there are fewer balls in total and one less white ball, so the probability for the second draw is 7/23. Continuing this for the third draw, the probability is 6/22. These probabilities need to be multiplied together to find the combined probability of selecting 3 white balls consecutively without replacement.

Thus, the probability of selecting 3 white balls in a row without replacement is:

(8/24) × (7/23) × (6/22) = (8 × 7 × 6) / (24 × 23 × 22) = 336 / (12,144)

After simplifying, the exact probability is 1/36.

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