SOLUTION: In a Gallup poll, 1025 randomly selected adults were surveyed and 29% of them said that they used the Internet for shopping at least a few times a year. Find the margin of error.

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Question 315101: In a Gallup poll, 1025 randomly selected adults were surveyed and 29% of them said that they used the Internet for shopping at least a few times a year.
Find the margin of error.
Find a 99% confidence interval estimate of the percentage of adults who use the Internet for shopping.
Answer by stanbon(75887) About Me  (Show Source):
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In a Gallup poll, 1025 randomly selected adults were surveyed and 29% of them said that they used the Internet for shopping at least a few times a year.
Find the margin of error.
Find a 99% confidence interval estimate of the percentage of adults who use the Internet for shopping.
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sample proportion: 0.29
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ME = (invT(0.995 with df = 1024)sqrt[0.29*0.71/1025] = 2.5806*0.0142 = 0.0366
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99% CI: 0.29-0.0366 < p < 0.29+0.0366
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Cheers,
Stan H.