problem defining distribution and probability

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Assume that 45% of the people in a city agree to implement a new social program ¿Which is the probability that in a sample of 2400 persons less than 1000 of them agree with the program?



First, I decided to model this like $X sim B(2400,.45)$, then I think we want to find $P(sum_i=1^2400 X_i<1000)$. Is it possible to model this like a Binomial or does it have to be distributed like a Bernoulli? Is the argument of the probability the one that I need?










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    Assume that 45% of the people in a city agree to implement a new social program ¿Which is the probability that in a sample of 2400 persons less than 1000 of them agree with the program?



    First, I decided to model this like $X sim B(2400,.45)$, then I think we want to find $P(sum_i=1^2400 X_i<1000)$. Is it possible to model this like a Binomial or does it have to be distributed like a Bernoulli? Is the argument of the probability the one that I need?










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      favorite











      Assume that 45% of the people in a city agree to implement a new social program ¿Which is the probability that in a sample of 2400 persons less than 1000 of them agree with the program?



      First, I decided to model this like $X sim B(2400,.45)$, then I think we want to find $P(sum_i=1^2400 X_i<1000)$. Is it possible to model this like a Binomial or does it have to be distributed like a Bernoulli? Is the argument of the probability the one that I need?










      share|cite|improve this question















      Assume that 45% of the people in a city agree to implement a new social program ¿Which is the probability that in a sample of 2400 persons less than 1000 of them agree with the program?



      First, I decided to model this like $X sim B(2400,.45)$, then I think we want to find $P(sum_i=1^2400 X_i<1000)$. Is it possible to model this like a Binomial or does it have to be distributed like a Bernoulli? Is the argument of the probability the one that I need?







      probability-distributions central-limit-theorem






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      edited Sep 1 at 3:54









      Javi

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      asked Sep 1 at 1:47









      Jorge Chang

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          Recall that a sum of Bernoulli-distributed random variables is a binomial random variable, so considering the Bernoulli variables $X_i$ independently or the sum of them as binomial, is the same.



          On the other hand, since you are adding 2400 (large number in this context) of those variables, using the central limit theorem you may safely approximate your binomial variable as normal variable.



          Finally, on the question regarding your probability $P(sum X_i < 1000)$, yes, this is what you are being asked to calculate.






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            1 Answer
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            1 Answer
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            active

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            up vote
            0
            down vote



            accepted










            Recall that a sum of Bernoulli-distributed random variables is a binomial random variable, so considering the Bernoulli variables $X_i$ independently or the sum of them as binomial, is the same.



            On the other hand, since you are adding 2400 (large number in this context) of those variables, using the central limit theorem you may safely approximate your binomial variable as normal variable.



            Finally, on the question regarding your probability $P(sum X_i < 1000)$, yes, this is what you are being asked to calculate.






            share|cite|improve this answer
























              up vote
              0
              down vote



              accepted










              Recall that a sum of Bernoulli-distributed random variables is a binomial random variable, so considering the Bernoulli variables $X_i$ independently or the sum of them as binomial, is the same.



              On the other hand, since you are adding 2400 (large number in this context) of those variables, using the central limit theorem you may safely approximate your binomial variable as normal variable.



              Finally, on the question regarding your probability $P(sum X_i < 1000)$, yes, this is what you are being asked to calculate.






              share|cite|improve this answer






















                up vote
                0
                down vote



                accepted







                up vote
                0
                down vote



                accepted






                Recall that a sum of Bernoulli-distributed random variables is a binomial random variable, so considering the Bernoulli variables $X_i$ independently or the sum of them as binomial, is the same.



                On the other hand, since you are adding 2400 (large number in this context) of those variables, using the central limit theorem you may safely approximate your binomial variable as normal variable.



                Finally, on the question regarding your probability $P(sum X_i < 1000)$, yes, this is what you are being asked to calculate.






                share|cite|improve this answer












                Recall that a sum of Bernoulli-distributed random variables is a binomial random variable, so considering the Bernoulli variables $X_i$ independently or the sum of them as binomial, is the same.



                On the other hand, since you are adding 2400 (large number in this context) of those variables, using the central limit theorem you may safely approximate your binomial variable as normal variable.



                Finally, on the question regarding your probability $P(sum X_i < 1000)$, yes, this is what you are being asked to calculate.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Sep 1 at 2:31









                Javi

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