SOLUTION: Sample with size n = 100 has mean = 30. Assuming the population standard deviation is 8, construct 95% confidence interval for population mean. Use formula zα/2 = 1.96
Ans
Algebra.Com
Question 716456: Sample with size n = 100 has mean = 30. Assuming the population standard deviation is 8, construct 95% confidence interval for population mean. Use formula zα/2 = 1.96
Answer ? Help?
between 28.4 and 31.6
between 27.0 and 33.0
between 26.1 and 34.2
between 24.1 and 35.9
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Lower Limit:
L = mean - za/2 * (standard deviation)/sqrt(n)
L = 30 - 1.96 * (8)/sqrt(100)
L = 30 - 1.96 * (8)/10
L = 30 - 1.96 * 0.8
L = 30 - 1.568
L = 28.432
Upper Limit:
U = mean + za/2 * (standard deviation)/sqrt(n)
U = 30 + 1.96 * (8)/sqrt(100)
U = 30 + 1.96 * (8)/10
U = 30 + 1.96 * 0.8
U = 30 + 1.568
U = 31.568
So the 95% confidence interval is (L, U) = (28.432, 31.568)
Round this to one decimal place to get (28.4, 31.6)
So the answer is Choice A) between 28.4 and 31.6
RELATED QUESTIONS
Please help
Sample with size n = 100 has mean = 30. Assuming the population standard... (answered by stanbon)
A sample of size n=26 has a sample mean x= 14.8 and a sample standard deviation s=2.6
(answered by jim_thompson5910)
A sample of size n=11 has a sample mean xbar=15.6 and sample standard deviation s=2.4.... (answered by ewatrrr)
A NORMAL POPULATION HAS STANDARD DEVIATION OF 10. A RANDOM SAMPLE OF SIZE 25 HAS A MEAN... (answered by stanbon)
A NORMAL POPULATION HAS STANDARD DEVIATION OF 10. A RANDOM SAMPLE OF SIZE 25 HAS A MEAN... (answered by Boreal)
I need some serious help please!
Find the appropriate confidence interval for the... (answered by stanbon)
2. A sample of size n = 20 is selected from a normal population to construct a 98%... (answered by stanbon)
Suppose a random sample of 50 values is taken from a normal population with standard... (answered by ewatrrr,stanbon)
You randomly select and weigh 30 samples of an allergy medicine and the sample standard... (answered by rothauserc)