Posted by Jana on Monday, December 20, 2010 at 2:14pm.
calculate the z scores:
z= (x-xbar)/(σ/sqrt(n))
where xbar=sample mean, σ=standard deviation of population, n=sample size, x=raw score (i.e. 98, 100)
now refer to the z chart:
http://www.thebeststatistics.info/sta/table_zvals.html
since you want the probability that the mean is between 98 and 100 months, I'd use the p-values on the right column (i.e. z-score to infinity) and take the difference of the p-values to get the area between 98 and 100.
Related Questions
Statistics - The average age of vehicles registered in the united states is 96 ...
probability and statistics - the average age for licensed drivers in the country...
statistics - The average age for licensed drivers in the county is μ &#...
statistics - The average age of a child in kindergarden is 5 years or 60 months...
statistics - At a large publishing company, the mean age of proofreaders is 36.2...
statistics - Speeds for a randomly selected sample of n = 36 vehicles will be ...
Statistics - An April 15, 2002 report in Time Magazine stated that the average ...
Statistics - The average age of chemical engineers is 37 years with a standard ...
business statistics - It has been reported that 10.3% of U.S. households do not ...
business statistics - It has been reported that 10.3% of U.S. households do not ...
For Further Reading
