Statistics

posted by .

. 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.

Similar Questions

1. statistics

A random sample of n=16 scores is obtained from a population with a mean of ยต= 80 and a treatment is administered to the sample. After treatment, the sample mean is found to be M=82. a)Assuming the sample contained n=16 individuals, …
2. statistics

The scores of students on the ACT college entrance examination in a recent year had a normal distribution with a mean of 18.6 and a standard deviation of 5.9. A simple random sample of 50 students who took the exam is selected for …
3. statistics

can anyone help me with this problem? a sample of n=9 indivividuals was selected from a normally distributed pop. with a mean of M=25 and a standard deviation of 6.a treatment was administered to the sample, and treatment , the nine
4. statistics

A sample of 40 observations is selected from one approximately normal population. The sample mean is 102 and the sample standard deviation is 5. A sample of 50 observations is selected from a second source. The sample mean is 99 and …
5. statistics

A sample of 40 observations is selected from one approximately normal population. The sample mean is 102 and the sample standard deviation is 5. A sample of 50 observations is selected from a second source. The sample mean is 99 and …
6. Statistics

he Oil Price Information Center reports the mean price per gallon of regular gasoline is \$ 3.79 with a population standard deviation of \$ 0.18. Assume a random sample of 40 gasoline stations is selected and their mean cost for regular …
7. statistics

10. A random sample of n=36 scores is selected from a normal distribution with a mean of u=60. After a treatment is administered to the individuals in the sample, the sample mean is found to be M=52.
8. Probabilty & Statistic

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 …
9. statistics

For normal population mean 60, standard deviation 15, after treatment is given to the member of sample , the sample mean is 65, and sample size is 25. is the sample mean sufficient to conclude that the treatment has significant effect?
10. statistics

A specific study found that the average number of doctor visits per year for people over 55 is 8 with a standard deviation of 2. Assume that the variable is normally distributed. 1. Identify the population mean. The population mean …

More Similar Questions