Conditioning on random variable











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Fish are caught at a rate of 3 every 2 hours. If a fisherman spends anywhere from 3 to 5.5 hours fishing on random day, find expectation and variance of number of fish he catches










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  • According to what distribution are the fish caught?
    – bob
    Dec 4 at 16:02















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Fish are caught at a rate of 3 every 2 hours. If a fisherman spends anywhere from 3 to 5.5 hours fishing on random day, find expectation and variance of number of fish he catches










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  • According to what distribution are the fish caught?
    – bob
    Dec 4 at 16:02













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Fish are caught at a rate of 3 every 2 hours. If a fisherman spends anywhere from 3 to 5.5 hours fishing on random day, find expectation and variance of number of fish he catches










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Fish are caught at a rate of 3 every 2 hours. If a fisherman spends anywhere from 3 to 5.5 hours fishing on random day, find expectation and variance of number of fish he catches







probability






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asked Dec 4 at 15:33









Murph Jones

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  • According to what distribution are the fish caught?
    – bob
    Dec 4 at 16:02


















  • According to what distribution are the fish caught?
    – bob
    Dec 4 at 16:02
















According to what distribution are the fish caught?
– bob
Dec 4 at 16:02




According to what distribution are the fish caught?
– bob
Dec 4 at 16:02










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Assuming that exactly 3 fish are caught every two hours, you would expect that if given from 3 to 5.5 hours, we would expect to catch anywhere between 4.5 and 8.25 fish. Assuming the fisherman decides his time fishing randomly between 3 and 5.5 hours, the number of caught fish could be represented by $X sim U[4.5, 8.25]$.



For uniform distribution: $$E[X] = dfrac{a+b}{2} = dfrac{4.5+8.25}{2} = 6.375$$ $$Var[X] = dfrac{(b-a)^2}{12} = dfrac{(8.25-4.5)^2}{12} approx 1.172$$






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    Assuming that exactly 3 fish are caught every two hours, you would expect that if given from 3 to 5.5 hours, we would expect to catch anywhere between 4.5 and 8.25 fish. Assuming the fisherman decides his time fishing randomly between 3 and 5.5 hours, the number of caught fish could be represented by $X sim U[4.5, 8.25]$.



    For uniform distribution: $$E[X] = dfrac{a+b}{2} = dfrac{4.5+8.25}{2} = 6.375$$ $$Var[X] = dfrac{(b-a)^2}{12} = dfrac{(8.25-4.5)^2}{12} approx 1.172$$






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      Assuming that exactly 3 fish are caught every two hours, you would expect that if given from 3 to 5.5 hours, we would expect to catch anywhere between 4.5 and 8.25 fish. Assuming the fisherman decides his time fishing randomly between 3 and 5.5 hours, the number of caught fish could be represented by $X sim U[4.5, 8.25]$.



      For uniform distribution: $$E[X] = dfrac{a+b}{2} = dfrac{4.5+8.25}{2} = 6.375$$ $$Var[X] = dfrac{(b-a)^2}{12} = dfrac{(8.25-4.5)^2}{12} approx 1.172$$






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        Assuming that exactly 3 fish are caught every two hours, you would expect that if given from 3 to 5.5 hours, we would expect to catch anywhere between 4.5 and 8.25 fish. Assuming the fisherman decides his time fishing randomly between 3 and 5.5 hours, the number of caught fish could be represented by $X sim U[4.5, 8.25]$.



        For uniform distribution: $$E[X] = dfrac{a+b}{2} = dfrac{4.5+8.25}{2} = 6.375$$ $$Var[X] = dfrac{(b-a)^2}{12} = dfrac{(8.25-4.5)^2}{12} approx 1.172$$






        share|cite|improve this answer












        Assuming that exactly 3 fish are caught every two hours, you would expect that if given from 3 to 5.5 hours, we would expect to catch anywhere between 4.5 and 8.25 fish. Assuming the fisherman decides his time fishing randomly between 3 and 5.5 hours, the number of caught fish could be represented by $X sim U[4.5, 8.25]$.



        For uniform distribution: $$E[X] = dfrac{a+b}{2} = dfrac{4.5+8.25}{2} = 6.375$$ $$Var[X] = dfrac{(b-a)^2}{12} = dfrac{(8.25-4.5)^2}{12} approx 1.172$$







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        answered Dec 4 at 16:07









        bob

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