1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Probability question ?

  1. May 4, 2009 #1
    [tools producing company packed them in boxes of 4.probability that a tool is satisfactory P.If the probability that a box contains at least 2 satisfactory tools is to be 0.95.show that 3P^(4) -8P^(3)+6P^(2)-0.95=0
    should be satisfy by P. How to approach this answer?
     
  2. jcsd
  3. May 4, 2009 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    Hi rclakmal! :smile:

    (try using the X2 tag just above the Reply box :wink:)
    Hint: probability that a tool is unsatisfactory is 1 - P.

    And probability that a box contains at least 2 satisfactory tools is 1 minus probability that it contains exactly 0 minus probability that it contains exactly 1. :wink:
     
  4. May 6, 2009 #3
    these days im fighting with the time o:) ..exam papers and theories are going simultaneously. after publishing this question i studied about binomial distribution .then i got to know that this problem should be solve by that .

    by using binomial theorem i was able to solve it as getting N=4 and r=2,3,4;
    then answer is
    0.95=SIGMA (r goes 2 to 4)= 4Cr*p^r*(1-p)
    then i got the answer .........thanks TINY TIM .........ur a great helping hand to me .....

    hoping ur help in the future also ......!:smile:
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Probability question ?
  1. A probability question (Replies: 3)

  2. Probability Question (Replies: 2)

  3. Probability Question (Replies: 12)

Loading...