Question

Write all formulas to receive full credit.

6. Suppose you are interested in estimating the percentage of all California high school students who passed the high school exit exam on the first try. If the goal is to estimate the percentage with 95% confidence and a margin of error 7%, how many current California high school students records should be sampled?

Answer 1

Solution :

Given that,

= 0.5

1 - = 0.5

margin of error = E = 0.07

At 95% confidence level the z is ,

= 1 - 95% = 1 - 0.95 = 0.05

/ 2 = 0.05 / 2 = 0.025

Z_/2 = Z _0.025 = 1.96

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

= (1.96 / 0.07)² * 0. * 0.5

= 196

196 high school students