Answer:
[tex]Z_{0.05}=1.645[/tex]
Step-by-step explanation:
Given :In a recent questionnaire about food, a random sample of 970 adults were asked about whether they prefer eating fruits or vegetables, and 458 reported that they preferred eating vegetables.
To Find :What value of z should be used to calculate a confidence interval with a 95 % confidence level?
Solution:
Confidence level = 95 % i.e.0.95
So, significance level = 5% i.e. 0.05
So, the value of z corresponding to significance level 0.05 should be used to calculate a confidence interval with a 95 % confidence level
So, [tex]Z_{0.05}=1.645[/tex]
Hence z should be 1.645 to calculate a confidence interval with a 95 % confidence level.