If selecting samples of size n 30 from a population with a known mean and standard deviation, what requirement, if any, must be satisfied in order to assume that the distribution of the sample means is a normal distribution?

Question

If selecting samples of size n > 30 from a population with a known mean and standard deviation, what requirement, if any, must be satisfied in order to assume that the distribution of the sample means is a normal distribution?

amistre64 · Answer

66-95-99 right?

amistre64 · Answer

the empirical rule; 66% fall within 1 sd of the mean

95% fall within 2 sd of the mean

and 99% fall within 3 sd of the mean

amistre64 · Answer

make sure my % are accurate tho lol

anonymous · Answer

The mean must be equal to the standard deviation. 
        The population must have a normal distribution. 
        None; the distribution of sample means will be approximately normal 
        The population must have a standard deviation of 0.

anonymous · Answer

To verify the empirical rule is your best bet, but you can also assume normal distribution if the sample size is greater than 30 and both (sample size)(probability of success) and (sample size)(probability of failure) are both greater than 5. But this is only if you are doing the assumption to approximate for binomial distribution

anonymous · Answer

those are the choices

amistre64 · Answer

it aint the first of the last..... my guess is 2

anonymous · Answer

thank u