Answer:
And rounded up we have that n=656
Step-by-step explanation:
In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 80% of confidence, our significance level would be given by
and
. And the critical value would be given by:
Solution to the problem
The margin of error for the proportion interval is given by this formula:
(a)
Since we don't have prior info for the proportion of interest we can use
as estimator. And on this case we have that
and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
And replacing into equation (b) the values from part a we got:
And rounded up we have that n=656
The expected value of the discrete distribution, if you have to pay $.50 to pick one package at random, is of -$0.08.
<h3>What is the mean of a discrete distribution?</h3>
The expected value of a discrete distribution is given by the <u>sum of each outcome multiplied by it's respective probability</u>.
For this problem, considering the cost of $0.5, the distribution is given as follows:
- P(X = 0.2) = 12/(12 + 15 + 23) = 12/50 = 0.24.
- P(X = -0.1) = 15/(12 + 15 + 23) = 15/50 = 0.3.
- P(X = -0.2) = 23/(12 + 15 + 23) = 23/50 = 0.46.
Hence the expected value is given by:
E(X) = 0.2 x 0.24 - 0.3 x 0.1 - 0.2 x 0.46 = -$0.08.
More can be learned about the expected value of a discrete distribution at brainly.com/question/13008984
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Answer:
8
Step-by-step explanation:
2^3 is the same as 2 x 2 x 2
2 x 2 is 4 and 4 x 2 is 8
so 2^3 is 8