Suppose a simple random sample of size n 1000 is obtained f
Solution
a)
By central limit theorem, it will have the same mean, u(p^) = 0.53.
However, the standard deviation is
sigma(p^) = sqrt(p(1-p)/n) = sqrt(0.53*(1-0.53)/1000)
= 0.015782902
Thus, it is OPTION B. [ANSWER, B]
***********************
b)
Note that P(at least x) = 1 - P(at most x - 1).
Using a cumulative binomial distribution table or technology, matching
n = number of trials = 1000
p = the probability of a success = 0.53
x = our critical value of successes = 570
Then the cumulative probability of P(at most x - 1) from a table/technology is
P(at most 569 ) = 0.993914889
Thus, the probability of at least 570 successes is
P(at least 570 ) = 0.006085111 [ANSWER]
Note that I used the binomial distribution here. Should you have another approach to this problem, please resubmit this question, stating the method you like, so we can help you! Thanks!
