Answer:
True.
Step-by-step explanation:
If we have for a sample of size n=25 a sample variance of 400, the standard error can be written as:
[tex]\sigma_s=\dfrac{\sigma}{\sqrt{n}}=\dfrac{\sqrt{400}}{\sqrt{25}}=\dfrac{20}{5}=4[/tex]
This way of calculating the standard error is the same used for estimating the standard deviation of the sample means for samples of size n=25.