If the students were to increase the sample size to n = 200 pieces of marbles each, what will the effect be on the center and variability of the sampling distribution?

Increasing the sample size does not change the expected center of the sampling distribution; it remains about the population value. But larger samples have less sampling variability: the standard error generally decreases as sample size increases, since it is proportional to 1/√n. Therefore, the center stays about the same while variability decreases, matching “The center would remain about the same. The variability would decrease.”

AI-written and checked against the verified answer.