Question

The American Fisheries Society is interested in the effect of mercury contamination on largemouth bass in Florida lakes. A sample of 53 fish were captured and the mercury concentration in the muscle tissue was measured (in ppm). The average mercury concentration of the sample is 0.525 ppm with a standard deviation of 0.348 ppm.

a. Find a 95% confidence interval for the mercury concentration in all largemouth bass in Florida lakes.

b. Find a 99% confidence interval for the mercury concentration in all largemouth bass in Florida lakes.

c. An AFS scientist claims that the mercury concentration is between 0.45 and 0.60 ppm. With what level of confidence can this statement be made?

Answer 1

#a. Find a 95% confidence interval for the mercury concentration in all largemouth bass in Florida lakes.

Ans

df = n-1 = 52

t = 2.0066

95% CI = (0.5250 - 2.0066*0.3486/sqrt(53) ,0.5250 + 2.0066*0.3486/sqrt(53) )

= ( 0.4289 , 0.6211 )

b. a 99% confidence interval for the mercury concentration in all largemouth bass in Florid

t = 2.6737

99% CI = (0.5250 - 2.6737*0.3486/sqrt(53) ,0.5250 + 2.6737*0.3486/sqrt(53) )

= ( 0.3970 , 0.6530 )

c) 95 %  level of confidence can this statement be made.that is An AFS scientist claims that the mercury concentration is between 0.45 and 0.60 ppm