Question 261280
The basic idea is that the more people you include the more normal the curve will appear. This is the idea of the law of large numbers. If I remember correctly, we want at least 30 people as our n. There might be pictures that show if n = 5, n = 10, n = 15, n = 30, n = 50 in your book.If we know that a distribution is normal, then we can apply our z - and t -scores as well as use confidence intervals, and degrees of freedom. This leads to accept or fail to accept the null hypothesis in some tests.
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hope that helps.