Central Limit Theorem:

To find the critical value zc, you need to set. The calculator code is: 0 = fnInt (y1,x,0,x) – c/2. If you have access to a t table, the values at the bottom can also be used for zc (on the ∞ line). b) If the population standard deviation is unknown, you should have a sample standard deviation s. Look up the critical value tc on a t table ... ................
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