This question is incomplete, the complete question is;
In order to determine an interval for the mean of a population with unknown standard deviation, a sample of 58 items is selected. The mean of the sample is determined to be 36. The associated number of degrees of freedom for reading the t value is :
a. 35.
b. 57.
c. 36.
d. 58.
Answer: Option b. 57 is the correct answer.
Explanation:
Given that;
sample size n = 58
sample mean x" = 36
degrees of freedom for reading the t value is = ?
we know that;
Degree of freedom df = n - 1
where n is the sample size
so we substitute
Degree of freedom df = 58 - 1
Degree of freedom df = 57
Therefore Option b. 57 is the correct answer.