The grade point averages for 10 randomly selected students in an algebra class with 125 students are listed below. What is the effect on the width of the confidence interval if the sample size is increased to 20?

width of the confidence interval decreases if the sample size is increased to 20.

Step-by-step explanation:

There are some factors which affect the width of the confidence interval such as:

The decrease in the sample standard deviation decreases the width of the interval .

The decrease the confidence level decreases the width of the interval .

The increase in the sample size decreases the width of the interval .

In the given question the previous sample size was 10 which was then increased to 20. So this increase in sample size causes the confidence interval to decrease. This is because when sample size increases, it decreases the standard error. This interprets that the sample size is getting closer to true population size.