Posted by Julia Brown on Friday, June 4, 2010 at 8:31pm.
The international Coffee Association has reported the mean daily coffee consumption for U.S. residents as 1.65 cups. Assume that a sample of 38 people from a North Carolina city consumed a mean of 1.84 cups of coffee per day, with a standard deviation of 0.85 cups. In a twotail test at the 0.05 level, could the residents of this city be said to be significantly different from their counterparts across the nation?

Statistics  PsyDAG, Saturday, June 5, 2010 at 11:09am
Z = (mean1  mean2)/standard error (SE) of difference between means
SEdiff = √(SEmean1^2 + SEmean2^2)
SEm = SD/√(n1)
Since only one SD is provided, you can use just that to determine SEdiff.
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related to the Z score. Is Z > 1.96?
Answer This Question
Related Questions
 Statistics  1) For each of the following statements, formulate appropriate null...
 Statistics: Percentile Rank  A survey of college students was conducted during ...
 biostatistics  among coffee drinkers, men drink a mean of 3.2 cups per day with...
 statistics  A survey of college students was conducted during final exam week ...
 Statistiscs  Students in the psychology department consume an average of 5 cups...
 statistics  In a study of caffeine and stress, college students indicate how ...
 math  the typical American coffee drinker consumes an average of 3.1 cups per ...
 statistics  Among coffee drinkers, men drink a mean of 2.8 cups per day with a ...
 Stats  1. In a study of caffeine and stress, college students indicate how many...
 Statistics: Calculate a Pearson's r  In a study on caffeine and stress, college...
More Related Questions