## anonymous 5 years ago 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?

1. amistre64

66-95-99 right?

2. amistre64

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

3. amistre64

make sure my % are accurate tho lol

4. anonymous

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.

5. anonymous

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

6. anonymous

those are the choices

7. amistre64

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

8. anonymous

thank u