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    (Original post by SeanFM)
    If you're looking for less than 5 in a discrete distribution, then the most it can be in a continuous distribution is 4.5. If it is less than or equal to 5, then the most it can be is 5.5.
    Whoops, I read it as '5 or less'
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    Please could anyone explain how we find the variance for exercise A question 3f https://771a1ec81340d97ae9ed29694f73...XZCVmc/CH3.pdf I understand how we find the mean, but I can't figure out the variance, thanks
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    (Original post by economicss)
    Please could anyone explain how we find the variance for exercise A question 3f https://771a1ec81340d97ae9ed29694f73...XZCVmc/CH3.pdf I understand how we find the mean, but I can't figure out the variance, thanks
    You know that X \sim N(\mu, \sigma^2) \Rightarrow \frac{X - \mu}{\sigma} \sim N(0, 1) (it's the standard normal!).

    Then \text{var}(X_1 + X_2 + \cdots + X_{10}) = 1 + 1 + 1 + 1 + \cdots + 1 = 10
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    Where can I find 2015 past paper??
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    (Original post by Armpits)
    Where can I find 2015 past paper??
    https://drive.google.com/folderview?...URWNGt0TU9nTnc
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    (Original post by Zacken)
    You know that X \sim N(\mu, \sigma^2) \Rightarrow \frac{X - \mu}{\sigma} \sim N(0, 1) (it's the standard normal!).

    Then \text{var}(X_1 + X_2 + \cdots + X_{10}) = 1 + 1 + 1 + 1 + \cdots + 1 = 10
    Oh yeah completely forgot that! Thank you
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    (Original post by paradoxequation)
    How do you solve the questions such as the part b one in the attached solution? I get the LHS, but I'm always a bit unclear on the steps from how they go from < 0.01 to < -2.3632. I understand they are using the percentage points but how exactly do you get there? Thanks.
    (Original post by paradoxequation)
    Sorry, forgot to attach...
    Anyone help please? Still don't understand.
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    (Original post by paradoxequation)
    Anyone help please? Still don't understand.
    So if you use the percentage points table in the formula book it gives us that the z value for the probability of being greater than 0.01 is 2.3263 however in this question we want the probability to be less than 0.01 so we need the negative of the z value so -2.3263, do you understand from there or would you like me to explain the rest? Hope that helps
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    (Original post by economicss)
    So if you use the percentage points table in the formula book it gives us that the z value for the probability of being greater than 0.01 is 2.3263 however in this question we want the probability to be less than 0.01 so we need the negative of the z value so -2.3263, do you understand from there or would you like me to explain the rest? Hope that helps
    Yep I get it now, thank you very much!
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    (Original post by paradoxequation)
    Yep I get it now, thank you very much!
    No problem
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    Could a question like this be asked in new papers? This was in Solomon Paper E which I'm sure is quite an old paper

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    (Original post by Euclidean)
    Could a question like this be asked in new papers? This was in Solomon Paper E which I'm sure is quite an old paper

    It actually has been asked in a past paper. 2012 iirc.
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    (Original post by Ayman!)
    It actually has been asked in a past paper. 2012 iirc.
    Cheers
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    Really struggling to find motivation to start revision for this
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    (Original post by Messier31)
    Really struggling to find motivation to start revision for this
    It's the same for nearly everyone :doh:
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    (Original post by Messier31)
    Really struggling to find motivation to start revision for this
    Mate thats ****ing everyone. This unit is so dead. I need to do some question on ch 4 and 5 still. Ch1-3 is calm tbh.


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    (Original post by Euclidean)
    It's the same for nearly everyone :doh:
    Not needing a good grade in it a doesn't help

    (Original post by physicsmaths)
    Mate thats ****ing everyone. This unit is so dead. I need to do some question on ch 4 and 5 still. Ch1-3 is calm tbh.


    Posted from TSR Mobile
    Is it bad that I don't even know the chapters :lol:

    Tempted to flunk it and start revising for FP2 but I'll probably do the questions by topic at least
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    (Original post by Messier31)
    Not needing a good grade in it a doesn't help
    I worked out I need 15 UMS :lol: but that's if I wanna fail AFM
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    (Original post by Euclidean)
    I worked out I need 15 UMS :lol: but that's if I wanna fail AFM
    Are you sure you can't throw it in regular maths or something? I can get 0 and it'll make no difference to anything :lol:

    Only reason for us to revise it is pride
 
 
 
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