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    ive done the first 2 parts fo this question but i dunno where to start on the last 3, help much appreciated, thanks

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    A brand of breakfast cereal is available in two sizes: the weights (in
    grammes) of the edible contents, and packaging are both Normally distributed
    with the following means and standard deviations:
    Edible contents Packaging
    Medium mean = 465, sd = 10 mean= 20, sd = 2
    Large mean = 625, sd = 15 mean = 25, sd = 3
    .
    Find the probabilities that
    1
    • a randomly chosen Large box has a total weight exceeding 640 grammes,
    • the total weight of the edible contents of 4 randomly chosen Large
    boxes exceeds 2450 grammes.
    • the edible contents of 4 randomly chosen Medium boxes weigh more
    than the edible contents of 3 randomly chosen Large boxes.
    • the total weight of 4 randomly chosen Medium boxes is more than
    the total weight of 3 randomly chosen Large boxes.
    • the total weight of 4 randomly chosen Medium boxes is more than
    the total weight of 3 randomly chosen Large boxes when each box
    also contains a small toy weighing exactly 50 grammes.
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    (Original post by eugenius 8)
    • the edible contents of 4 randomly chosen Medium boxes weigh more
    than the edible contents of 3 randomly chosen Large boxes.
    For part 3, you're looking for P(M_1+M_2+M_3+M_4 > L_1+L_2+L_3)

    Or rearranging you're looking for: P(M_1+M_2+M_3+M_4 -L_1-L_2-L_3> 0)

    So, the question is, what's the distribution of M_1+M_2+M_3+M_4 -L_1-L_2-L_3

    Since you've done part 2, you can probably have a good stab at that.
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    What module is this?
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    (Original post by ghostwalker)
    For part 3, you're looking for P(M_1+M_2+M_3+M_4 > L_1+L_2+L_3)

    Or rearranging you're looking for: P(M_1+M_2+M_3+M_4 -L_1-L_2-L_3> 0)

    So, the question is, what's the distribution of M_1+M_2+M_3+M_4 -L_1-L_2-L_3

    Since you've done part 2, you can probably have a good stab at that.
    cheers, that really helped

    (Original post by Hoody93)
    What module is this?
    its a statistical methods module for an accounting degree
 
 
 
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