S1 question.. Need help please

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  1. Abed1993's Avatar
    • Benevolent Member
    • Location: Lozells
    • Posts: 738
    S1 question.. Need help please
    Bob has 10 seeds. The probability of one of them germinating is 0.15..

    Find the probability exactly 5 of them germinate..

    What I did

    P(x=0) +P(x=1) +P(x=2) +P(x=3) +P(x=4) +P(x=5)

    I did the work out using the nCr method..

    and the answer i got was wrong ..

    What did i do wrong?
    Last edited by Abed1993; 19-04-2012 at 17:15.
  2. Abed1993's Avatar
    • Benevolent Member
    • Location: Lozells
    • Posts: 738
    Re: S1 question.. Need help please
    I think i may found out..

    was i meant to do

    P(x=5) +P(x=6) +P(x=7) +P(x=8) +P(x=9) +P(x=10)

    ??
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