Alkalinity of river water. In Exercise 5. 26 (p. 183) learned that the mean alka
ID: 3150279 • Letter: A
Question
Alkalinity of river water. In Exercise 5. 26 (p. 183) learned that the mean alkalinity level of water specimen collected from the Han River in Seoul. Korea, is 50 milligrams per liter. (Environmental Science & Engineenn&a; September 1. 2000.) Consider a random sample of 100 water specimens collected from a tributary of the Han River. Suppose the mean and standard deviation of the alkalinity levels for the sample are v=67. 8 mg/L and. V=14. 4 mg/L. Is there sufficient evidence (at a=. 01) j to indicate that the population mean alkalinity level of water in the tributary exceeds 50 mg/L?Explanation / Answer
H0: mu = 50
Ha: mu >50
Right tailed test
Mean difference = 67.8-50 = 17.8
Std error - 14.4/10 = 1.44
test statistic = 17.8/1.44 = 12.36
p value = 0
Since p < alpha reject null hypothesis
and accept mean >50