MATH SOLVE

4 months ago

Q:
# In a poll, 74% of the people polled answered yes to the question "Are you in favor of the death penalty for a person convicted of murder?" The margin of error in the poll was 4%, and the estimate was made with 90% confidence.How many people were surveyed?How do you step by step solve this with a TI-84 Calculator? What function can you use?

Accepted Solution

A:

Answer:324Step-by-step explanation:given that in a poll, 74% of the people polled answered yes to the question "Are you in favor of the death penalty for a person convicted of murder?"i.e. Sample proportion [tex]p=0.74\\q =1-p =0.26\\[/tex]Margin of error = 4% = 0.04Confidence level =90%Z critical value for 90% = 1.645Margin of error = 1.645 * std errorHence std error = [tex]\frac{0.04}{1.645} \\=0.0243[/tex]Std error is also equal to[tex]\sqrt{\frac{pq}{n} } =\sqrt{\frac{0.74(0.26)}{n} } =0.0243\\\sqrt{n} =18..05\\n = 325.83~324[/tex]Sample size should be 324.The formula is sample size = (Z critical value)^2 (pq)/(Margin of error )^2