When finding a confidence interval for a population mean based on a sample of size 8, which assumption is made?
A) The population standard deviation,is known.
B) The sampling distribution of z is normal.
C) The sampled population is approximately normal.
D) There is no special assumption made.
E) None of these.

Question

Quizplus · Accepted Answer

When finding a confidence interval for a population mean based on a sample of size 8, the assumption made is that the sampled population is approximately normal. This is because the central limit theorem states that for sample sizes larger than 30, the sample mean will be approximately normally distributed regardless of the shape of the population distribution. However, for sample sizes smaller than 30, the population distribution should be approximately normal to ensure the validity of the confidence interval. Therefore, option C is the best choice.

When Finding a Confidence Interval for a Population Mean Based