Menhaden are an abundant, but inedible, ocean fish of the Atlantic and Gulf wate
ID: 3067285 • Letter: M
Question
Menhaden are an abundant, but inedible, ocean fish of the Atlantic and Gulf waters that are harvested commercially as a nutritional source of omega-3 fatty acid. They are ground up for fish meal and fertilizer and also serve as a major food source for sea bass and other more commercial fish. The lengths of menhaden are approximately normally distributed with a mean length of 12 inches and a standard deviation of 2.5 inches. If you were to commercially catch 20,000 menhaden, which one of the following intervals would you expect to contain approximately 8000 menhaden? (A) (B) (C) 0 to 11.87 inches 8.80 to 12.5 inches 8.80 to 15.20 inches 10.69 to 13.31 inches 10.69 to 14.10 inches (D) (E) 41Explanation / Answer
for 8000 is equaivalent to 8000/20000 =0.4 middle proportion for which lies between 30th and 70 th percentile
for 30th and 70 th percentile ; z score =0.5244
therefore corresponding value =mean -/+ z*std deviaiton =10.69 to 13.31
option D is correct