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    40cm ribbon is cut into two at a random point. The R.V. 'X' represents length of the shorter piece in cm.

    Specify the probability distribution of X.

    Bit stuck. All I can work out is that the distribution is continuous because X could have like 10000 decimal places so it's not discrete, and that P(0<X<20) = 1 as otherwise it's a negative length or it's not the shortest ribbon.

    Can anyone nudge me in the right direction?
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    (Original post by Fudge2)
    40cm ribbon is cut into two at a random point. The R.V. 'X' represents length of the shorter piece in cm.

    Specify the probability distribution of X.

    Bit stuck. All I can work out is that the distribution is continuous because X could have like 10000 decimal places so it's not discrete, and that P(0<X<20) = 1 as otherwise it's a negative length or it's not the shortest ribbon.

    Can anyone nudge me in the right direction?
    the required distribution is uniform continuous (Rectangular) distributed over the interval [0,20]

    do you know how to specify the pdf?
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    (Original post by TeeEm)
    the required distribution is uniform continuous (Rectangular) distributed over the interval [0,20]

    do you know how to specify the pdf?
    Is specifying it where I would say f(x) = 1/20 for 0<x<20 and 0 otherwise? At least I think that's what it would be?

    So it's rectangular because the probability of cutting it at any point is the same as cutting it at any other point if that makes sense?

    Thanks
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    Goodness, that's a badly worded question! Strictly speaking there isn't enough information to answer it. Cut at a "random" point does not imply cut at a uniformly distributed random point...
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    (Original post by Fudge2)
    Is specifying it where I would say f(x) = 1/20 for 0<x<20 and 0 otherwise? At least I think that's what it would be?

    So it's rectangular because the probability of cutting it at any point is the same as cutting it at any other point if that makes sense?

    Thanks
    correct
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    (Original post by Gregorius)
    Goodness, that's a badly worded question! Strictly speaking there isn't enough information to answer it. Cut at a "random" point does not imply cut at a uniformly distributed random point...
    standard current A level vocabulary
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    (Original post by TeeEm)
    standard current A level vocabulary
    Oh my. No wonder I have reprogramme students when they arrive at university
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    (Original post by Gregorius)
    Goodness, that's a badly worded question! Strictly speaking there isn't enough information to answer it. Cut at a "random" point does not imply cut at a uniformly distributed random point...
    Haha yeah I struggled to make the connection! Glad it isn't just me who thought it was weird

    (Original post by TeeEm)
    correct
    Awesome thanks. I can't rep you apparently so PRSOM.
 
 
 
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