Question

IQ is known to follow a normal distribution with a mean of 100 and a standard deviation of 15. If we chose a sample of 10 people, explain in one or two sentences why the distribution would still be considered normal even though the amount of people were under 30.

Answer 1

Explanation:

According to the central limit theorem, a distribution is said to be normal if the sample size is sufficiently large (usually n > 30) notwithstanding whether the source population is normal or skewed. But for a population that is normally distributed the theorem still holds true. for samples smaller than 30.

The shape of the sampling distribution changes with a sample size. For a large sample size, the sampling distribution starts to approximate a normal distribution.