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Probability questions

Discussion in 'DAT Discussions' started by Awuah29, Apr 20, 2004.

  1. Awuah29

    Awuah29 Christian predent
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    Anyone out there who know how to solve these two problems :

    If two dice are rolled, what is the probability of rolling a total of 4?

    There are 4 black balls and 7 white balls in a drawer. If two balls are drwan at random ( one after the other without replacement) what is the probability of selecting two black balls?

    Thanks guys :) :thumbup:
     
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  3. busdriver

    busdriver what do i know?
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    for the balls one:
    11 balls total. 4 black balls. 4/11 times 3/10 should give you the probability of two black balls. so i guess 12/110 or 6/55

    for the dice one. to get a total of four you can get 1 and 3, 2 and 2, and 3 and 1 so since there's 36 possibilites total for dice, it would be 3/36 or 1/12

    please correct me if i'm wrong...it's been awhile since i've done probability...
     
  4. sxr71

    sxr71 Senior Member
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    You're right!
     

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