Answer:
b. the average calorie count of a large number of fruit smoothie brands has a sampling distribution that is close to Normal.
Explanation:
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean
and standard deviation
, the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean
and standard deviation
.
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
Applying to this question:
The distribution of the number of calories in fruit smoothies is strongly skewed to the right. However, in a sample with a large number of fruit smoothies, the sampling distribution will be approximately normal, so the correct answer is given by option B.