Question 1033601
The sample mean is 575 / 1280 = 0.449 approx 0.45
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The sample standard deviation is square root(0.45*0.55/1280) =  0.0139 approx 0.01
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95% lower = 0.45 - (0.01 * 1.96) = 0.4304 approx 0.43
95% higher = 0.45 + (0.01 * 1.96) = 0.4696 approx 0.47
:
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95% CI = (0.43, 0.47)
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:
The new sample mean is 1150 / 2560 = 0.4492 approx 0.45
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The new sample standard deviation is square root(0.45*0.55/2560) = 0.0098 approx 0.01
:
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The new 95% CI is the same
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