Here's the question:
A recent Gallup Poll interviewed a random sample of 1523 adults. Of these, 868 bought a lottery ticket in the past year.Suppose that in fact (unknown to Gallup) exactly 60% of all adults bought a lottery ticket in the past year. If Gallup took many SRSs of 1523 people, the sample proportion who bought a ticket would vary from sample to sample. The sampling distribution would be close to normal with
a)mean 0.6 and standard deviation 0.00016
b)mean 0.6 and standard deviation 0.0126
c)mean 0.6 and standard deviation 0.4899
d)mean 0.6 and standard deviation 0.0251
I am stumped at the point in the problem where I have to find the z-score and multiply it with the standard deviation. I found the standard deviation to be .013, but I don't know what z-score to multiply it with.
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