Question

Use the given data to find the minimum sample size required to estimate a population proportion or percentage. Margin of error: nine percentage points; confidence level 90 %; from a prior study, ModifyingAbove p with caret is estimated by the decimal equivalent of 56 % nequals nothing (Round up to the nearest integer.)

Answer 1

Solution :

Given that,

= 56% = 0.56

1 - = 1 - 0.56 = 0.44

Margin of error = E = 9% = 0.09

At 90% confidence level the z is ,

= 1 - 90% = 1 - 0.90 = 0.10

/ 2 = 0.10 / 2 = 0.05

Z_/2 = Z_0.05 = 1.645

Sample size = (  Z_/2 / E)² * * (1 - )

= (1.645 / 0.09)² * 0.56 * 0.44

= 82.31 = 83

Sample size = n = 83