SOLUTION: An urn has 7 balls that are identical except that 3 are white and 4 are red. A sample of 4 is selected randomly without replacement. What is the probability that exactly 2 are whi

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Question 1204024: An urn has 7 balls that are identical except that 3 are white and 4 are red. A sample of 4 is selected randomly without replacement.
What is the probability that exactly 2 are white and 2 are red?

What is the probability that at least 2 of the balls are white?

Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20849)   (Show Source): You can put this solution on YOUR website!

balls that are identical except that are white and are red

What is the probability that exactly are white and are red?


What is the probability that at least of the balls are white?


Answer by ikleyn(52776)   (Show Source): You can put this solution on YOUR website!
.
An urn has 7 balls that are identical except that 3 are white and 4 are red.
A sample of 4 is selected randomly without replacement.
(a) What is the probability that exactly 2 are white and 2 are red?
(b) What is the probability that at least 2 of the balls are white?
~~~~~~~~~~~~~~~~~~~~~~~~~


        In the post by  @MathLover1,  her solution and the answer for part  (b)  both are  INCORRECT.
        I came to bring a correct solution for part  (b).


    P =  =  = .    ANSWER

Solved (correctly).

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To see many other similar  (and different)  problems solved,  look into the lesson
    - Elementary Probability problems related to combinations
in this site.

Learn the subject from there.



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