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    Here is a very rough unofficial mark scheme.

    Anything in bold is what I am unsure of and still need confirmation. I have missed out the explanation questions as well cant remember them.

    If you know anything please let me know so I can add it in!
    ---------------------------------------------

    1. (Bee wiggles)

    PMCC = 0.99
    b=?
    a=?
    estimate = 3.581

    2. (Discrete Random Variables)
    a) Making equation
    b and c) q = 0.15 and p = 0.175
    d) E(R) = 0.45
    f) Couldn't do the last part

    3. (Seatrop question)

    s.d = 2.51 (I used the equation that represented the sample, not the population, so might be slightly different)
    Sxy = -133.9
    PMCC = -0.7

    4. (Venn diagram question?)
    a) 0
    b) u = 0.03 t = 0.22
    d) P(D|RnB) = 0.45 P(D|RnB' = 0.405
    f) 16 students

    5. (Baby question)

    a) Width = 0.5 Height = 17
    b) Median = 3.47
    c) Mean = 3.43
    d) Standard Distribution part i can't remember

    6. (Normal Distribution)
    a) ?
    b) Maximum time was 206 minutes
    c) P(W < u -30| W < u) = 0.36
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    What was the last part's question for #2?
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    (Original post by Sels97)
    What was the last part's question for #2?
    It was the one where you had to find the probability that sarah wins or rebecca wins
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    (Original post by SirRaza97)
    It was the one where you had to find the probability that sarah wins or rebecca wins
    IIRC Rebecca could only win when X was 1/2 and therefore she had a 0.2 chance of winning, whereas Sarah had a 0.8 chance.

    I could be wrong, but this is the conclusion I came to
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    with that question i'm pretty sure there was the opportunity that they could draw too instead of winning/losing I think I got 0.65 for sarah and 0.2 for rebecca
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    4 D) P(D|RnB) = 0.45 P(D|RnB') = 15/37
    E) 33 People
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    (Original post by M3WIZARD)
    4 D) P(D|RnB) = 0.45 P(D|RnB' = 15/37
    E) 33 People
    15/37 is the same as 0.405 just rounded. How did you get 33?
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    I got 16 for the people who will have dinner too
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    I got 33 people for dinner
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    I got 33. Also I don't think that the dimensions for the bar on the histogram is right? I didn't get that, but I could be wrong - always struggle with histograms.
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    (Original post by LordStark)
    I got 33. Also I don't think that the dimensions for the bar on the histogram is right? I didn't get that, but I could be wrong - always struggle with histograms.
    Mate I got 33 aswell. Always encouraging to hear that someone else got a similar answer. 😊
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    For 2f), I got that the probability Sarah wins is 0.475 and the probability Rebecca wins is 0.375.

    From what i remember from my working out, Sarah can only win when X=3/2 and 2 so thats (0.3+0.175) and Rebecca can only win when X=-2 and 1/2 (0.175+0.2). There was a probability of drawing when X=-1 (0.15).

    I could be wrong though. Did anyone else get this?
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    (Original post by Jorjio)
    For 2f), I got that the probability Sarah wins is 0.475 and the probability Rebecca wins is 0.375.

    From what i remember from my working out, Sarah can only win when X=3/2 and 2 so thats (0.3+0.175) and Rebecca can only win when X=-2 and 1/2 (0.175+0.2). There was a probability of drawing when X=-1 (0.15).

    I could be wrong though. Did anyone else get this?
    I got the same!
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    1.) one question was which was the response variable, i said the number of bee wiggles is that right?
    Also got something like w = 0.722 + 0.0142d for the regression line

    4) last part i got 33 dinners, and i think thats right. you had to use the ratio of how many people ordered dessert to how many didn't from each of the two groups out of 77. There was a really similar question on one of the recent IAL papers

    5f.) I said:
    The mean and median are very similar = data is fairly symmetrical = good idea to use n.dis.
    But worked out in part (d) that 25% of the babies weigh less than 3kg. Whereas the table showed that only 9/50 babies weighed less than 2 (=18%). Therefore Shyam should refine her model to make it more accurate.

    6a.) what proportion finished in ?over/under? 300 minutes: 6.68%
 
 
 
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