SOLUTION: An urn contains 10 red balls and 15 white balls. A ball is selected at random from the urn and not replaced. Then, a second ball is selected. Show that the probability that the sec

Algebra ->  Probability-and-statistics -> SOLUTION: An urn contains 10 red balls and 15 white balls. A ball is selected at random from the urn and not replaced. Then, a second ball is selected. Show that the probability that the sec      Log On


   

Question 352896: An urn contains 10 red balls and 15 white balls. A ball is selected at random from the urn and not replaced. Then, a second ball is selected. Show that the probability that the second ball is red is the same as the probability that the first ball is red.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
An urn contains 10 red balls and 15 white balls. A ball is selected at random from the urn and not replaced. Then, a second ball is selected. Show that the probability that the second ball is red is the same as the probability that the first ball is red.
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P(red on 1st draw) = 10/25
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Note: The red is NOT replaced.
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P(red on 2nd draw) = 9/24
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Note: These probabilities are NOT the same.
They would be if you had replaced the 1st red drawn.
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Cheers,
Stan H.