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    Could someone provide me with clear explanation of how to complete this question.

    Many thanks.
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    (Original post by greentron6)
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    Could someone provide me with clear explanation of how to complete this question.

    Many thanks.
    What have you done/ tried to do?

    The first step with histogram / interval data is to convert the endpoints to true values.

    The next thing you need to do for this question is to work out the total number of people >24.5 and the total sample size.
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    Do what the guy said above then just multiply the probability value you get
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    (Original post by googleit)
    Do what the guy said above then just multiply the probability value you get
    Im still confused. Could you actually do the question for me, so I can understand better...
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    (Original post by lerjj)
    What have you done/ tried to do?

    The first step with histogram / interval data is to convert the endpoints to true values.

    The next thing you need to do for this question is to work out the total number of people >24.5 and the total sample size.
    Thanks for replying!
    Im still confused. Could you actually do the question for me, so I can understand better...
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    (Original post by greentron6)
    Thanks for replying!
    Im still confused. Could you actually do the question for me, so I can understand better...
     P (t > 24.5) = \dfrac{ 8 + 3}{2+9+20+13+8+3}
     P=0.2
    (Because it asks for over 24.5, that's just the last two entries. If it asked for e.g. 24.3 you'd need to interpolate a little instead of just adding up the numbers in the last two boxes)

    Edit: Misread the question - it says that there are two phone calls. That means that this is a "drawing without replacement" style question. The probability that the first call is >24.5minutes is still 11/55, but the second call now has a probability of 10/54 since you presumably made sure it wasn't the same call. So the combined probability is 1/27.
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    This is new to me. Is this still on the spec?
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    (Original post by lerjj)
     P (t > 24.5) = \dfrac{ 8 + 3}{2+9+20+13+8+3}
     P=0.151
    (Because it asks for over 24.5, that's just the last two entries. If it asked for e.g. 24.3 you'd need to interpolate a little instead of just adding up the numbers in the last two boxes)
    How did you get that answer? I did it with the z = X - Mean / Standard deviation
    and the used the probability table to get the answer. Which is 0.56155
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    (Original post by greentron6)
    This is new to me. Is this still on the spec?
    Yes, it's a simple probability question.
 
 
 
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