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Is this an appropriate layout of a normal distribution question (calc) (image shown) Watch

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    hey guys,
    this image was scanned in from a past paper question which I did using a calculator. Is this a suitable way to lay out my answer when using a calculator??

    Just so you know, the top answer was the answer to: P(V>420) mean=412 s=8.
    and the bottom answer was the answer to the question P(V=410) with means and standard deviations the same as last question. (but got it wrong haha).


    Thanks
    Dan

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    The only improvement really would be to put the 420 on your top diagram and 410 on the bottom, do you understand as to why P(V=410) = 0?
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    that is one question i never seem to get :P is it because normal distributions cannot be exact??
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    Yeah, normal distributions are made from whats known as 'continuous data' things such as height or weight which is only as accurate as the equipment used to measure it.

    For example:

    A man can weigh 120kg or 119.8kg or 119.842359kg.

    All are essentially the same number just increasingly more accurate. Normal distributions are made up of such data, the alternative being discrete such as the number you can roll on a dice, it is always a fixed integer.

    So to get to the point, because there are so many millions of exact data values the actual probabolity of selecting one of these values exactly is so miniscule we just say the probablity of P(X=N), where N is an exact value, is 0
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    ahhh right. thanks mate! Now i know why that question was only one mark :P.

    btw, nice clear explanation
 
 
 
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