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    I'm stuck on part (ii)

    How do I solve when there are two inequalities?

    I'm also stuck on part (iv). Is this a probability distribution now?

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    What part (iv) is saying is that X_1 \sim \text{Geo}(0.2) and X_2 \sim \text{Geo}(0.2); you have to find \mathbb{P}(X_1 + X_2 = 3), which you can work out by considering possible combinations of X_1, X_2 and their probabilities.
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    (Original post by nuodai)
    What part (iv) is saying is that X_1 \sim \text{Geo}(0.2) and X_2 \sim \text{Geo}(0.2); you have to find \mathbb{P}(X_1 + X_2 = 3), which you can work out by considering possible combinations of X_1, X_2 and their probabilities.
    That made no sense whatsoever. Explain further please. Do you mean I should use combinations?

    3C1(0.2)^2(0.8)^1=0.096

    ??
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    (Original post by nuodai)
    What part (iv) is saying is that X_1 \sim \text{Geo}(0.2) and X_2 \sim \text{Geo}(0.2); you have to find \mathbb{P}(X_1 + X_2 = 3), which you can work out by considering possible combinations of X_1, X_2 and their probabilities.
    Help! :mad:
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    (Original post by No!)
    Help! :mad:
    I would have before you said that I'm not paid to do this you know.
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    (Original post by nuodai)
    I would have before you said that I'm not paid to do this you know.
    ok I'm just so angry because I don't understand the question. I don't understand what you implied to do. I'm not good at maths, please explain it more simply.
 
 
 
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