Posted by **Sharon** on Monday, January 23, 2012 at 4:39pm.

A random sample is selected from a normal population with a mean of __40 and a standard deviation of __10. After a treatment is administered to the individuals in the sample, the sample mean is found to be M _ 42.

a. How large a sample is necessary for this sample mean to be statistically significant? Assume a two tailed test with _ = .05

b. If the sample mean were M _ 41, what sample size is needed to be significant for a two-tailed test with _ = .05.

## Answer this Question

## Related Questions

- Statistics - . A random sample is selected from a normal population with a mean ...
- statistics - 10. A random sample of n=36 scores is selected from a normal ...
- Statistic - A random sample of size 20 drawn from a normal distribution has a ...
- statistics - For normal population mean 60, standard deviation 15, after ...
- statistics - A random sample of n=16 scores is obtained from a population with a...
- Math (Statistic) - Considered the sampling distribution of a sample mean ...
- statistics - can anyone help me with this problem? a sample of n=9 indivividuals...
- statistics - A sample of 40 observations is selected from one approximately ...
- statistics - A sample of 40 observations is selected from one approximately ...
- statistics - A specific study found that the average number of doctor visits per...