Question

In a situation where the population standard deviation was increased from 3.1 to 5.8, what would be the impact on the confidence interval?
A. It would remain the same as standard deviation does not impact confidence intervals
B. It would become narrower due to the increased population standard deviation
C. It would become narrower with more values
D. It would become wider due to the increased population standard deviation

Answer 1

Answer:

Option D:

Step-by-step explanation:

The formula for confidence interval is;

CI = x¯ ± z√σ

Where σ is population standard deviation.

Now, increasing the value of σ means that z√σ will increase and thus, the width of the confidence interval will in turn become wider since z√σ is added to and subtracted from x¯.

Correct answer is option D.