Answer:
Explained below.
Step-by-step explanation:
According to the Central Limit Theorem if an unknown population is selected with mean μ and standard deviation σ and appropriately huge random samples (n > 30) are selected from this population with replacement, then the distribution of the sample means will be approximately normal.
Then, the mean of the sampling distribution of sample means is given by,
[tex]\mu_{\bar x}=\mu[/tex]
And the standard deviation of the sampling distribution of sample means is given by,
[tex]\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}}[/tex]
So, if the sample of daily calcium intake of Americans collected is more than 30, then the sampling distribution of [tex]\bar X[/tex] will be approximately normal.