0
$\begingroup$

There are 9 wrapping bags, 3 of which contains 2GB pen drive, and the rest contains 1 GB Pendrive. There are 3 girls and 5 boys randomly select a bag each. Find the probability that

i) the girls select more bags which contains 2GB pendrive than the boys ii) none of the girls has a bag which contain 2GB pendrive

Just wanna make sure, for

i) is it P(X more and equal to 2) where n=3, r=2 & 3 respectively, p=1/3 while q=2/3

ii) is it P(X=O) whr n=3, r=0, p=2/3, q=1/3 ?

  • 0
    Ahh my bad, it's supposed to be 2GB instead of 3GB. Sorry – 2017-02-14
  • 0
    To your question: it looks like you are treating this like a binomial distribution, but that isn't right since (presumably) the kids choose without replacement. Thus, while the first kid has a $\frac 13$ chance of drawing a 2GB drive, the second kid's chances depend on what the first kid drew. – 2017-02-14
  • 0
    Hint: go case by case: what is the probability that the girls draw exactly two? what is the probability that they draw three? – 2017-02-14
  • 0
    Hint 2: probability functions for Hypergeometric distributions involve binomial coefficients, re: The probability for selection of $k$ from $K$ 'successes" and $(n-k)$ from $(N-K)$ "failures" when selecting and $n$ from $N$ items. – 2017-02-14
  • 0
    What is n-K ? ^^;; I'm sorry but my Statistic knowledge and understanding are very basic...as I'm also learning the basic Stats only ^^;; – 2017-02-16

0 Answers 0