00:01
So for this problem, we run into a little bit of a pet peeve that i have with statistics, and that is that the rules vary.
00:16
So we're asked, which condition must be met in order to use the normal approximation in a z -test for proportions? i've seen some books say that the number of successes, which we could say x, or the expected number of successes, that is, should be greater than or equal to five, and the number of expected number of failures and minus x should also be greater than or equal to five.
00:43
I've also seen that the expected number of successes must be greater than or equal to 10, and the expected number of failures must be greater than are equal to 10, and i've also also seen that the expected number of successes times the expected number of failures must be greater than or equal to 10.
01:00
Without having your textbook, i don't, i can't tell which exactly is going to be the expectation here.
01:08
So, for determining what is the correct answer, we are mostly going to need to look carefully at the information that we have and what is being discussed.
01:19
So we know that n is always going to be the sample size.
01:29
And we should be careful.
01:31
I typically use the symbol p hat to represent the sample proportion, but basically, so let's see here, i would use p hat to represent the sample proportion and p to represent the population proportion, or another notation...