How do we know that our sample is enough to represent the population in statistics?

I'm going to make a test about paired samples. They're non parametric samples. But i confused wether the samples is not enough to represent the population. So how do we know or what test should i do to make sure the sample is quite enough.


Thanks

How do we know that our sample is enough to represent the population in statistics?
If you are doing a paired-sample t-test, the rule of thumb would be a minimum of 30 participants, assuming the responses are normally distributed on both the pre- and post-tests.





My understanding is that in computer simulations drawing lots of different samples from a virtual population, n=30 is the smallest sample that has an acceptable probability of approximating a normal distribution.





If you want to do any regression or factor analyses, you should have a least n=100.