Question

In: Statistics and Probability

​It's believed that as many as 23​% of adults over 50 never graduated from high school....

​It's believed that as many as 23​% of adults over 50 never graduated from high school. We wish to see if this percentage is the same among the 25 to 30 age group. What sample size would allow us to increase our confidence level to​ 95% while reducing the margin of error to only 2​%?

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Expert Solution

Solution :

Given that,

= 0.23

1 - = 0.77

margin of error = E = 0.02

Z/2 = 1.96

sample size = n = (Z / 2 / E)2 * * (1 - )

= (1.96 / 0.02)2 * 0.23 * 0.77

= 1701

sample size = n = 1701

orchestra answered 3 years ago
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