Answer:
C= 95%, = 0.40,
1)
for n= 100
formula for confidence interval is
Where Zc is the z critical value for Zc = 1.96
0.304 < P < 0.496
thus we get confidence interval = ( 0.304 , 0.496)
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2)
for n = 1000
formula for confidence interval is
Where Zc is the z critical value for Zc = 1.96
0.370 < P < 0.430
thus we get confidence interval = ( 0.370 , 0.430)
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3)
for n = 10000
formula for confidence interval is
Where Zc is the z critical value for Zc = 1.96
0.390 < P < 0.410
thus we get confidence interval = ( 0.390 , 0.410)
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Width of confidence interval decreases as the sample size increases.
because, as sample size increases the standard error is decreases.
Hence, Width of confidence interval decreases.
For each of the following three sample sizes, con- struct the 95% confidence interval. Use a...
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