Salmon Weights: Assume that the weights ofspawning Chinook salmon in the Columbia river are normallydistributed. You randomly catch and weigh 18 such salmon. The meanweight from your sample is 22.2 pounds with a standard deviation of4.7 pounds. You want to construct a 99% confidence interval for themean weight of all spawning Chinook salmon in the ColumbiaRiver.
(a) What is the point estimate for the mean weight of allspawning Chinook salmon in the Columbia River?
pounds =
(b) Construct the 99% confidence interval for the mean weight ofall spawning Chinook salmon in the Columbia River. Roundyour answers to 1 decimal place.
? < ? < ?
(c) Are you 99% confident that the mean weight of all spawningChinook salmon in the Columbia River is greater than 20 pounds andwhy?
No, because 20 is above the lower limit of the confidenceinterval.
Yes, because 20 is below the lower limit of the confidenceinterval.
No, because 20 is below the lower limit of the confidenceinterval.
Yes, because 20 is above the lower limit of the confidenceinterval.
(d) Recognizing the sample size is less than 30, why could we usethe above method to find the confidence interval?
Because the sample size is less than 100.
Because the sample size is greater than 10.
Because the parent population is assumed to benormally distributed.
Because we do not know the distribution of the parentpopulation.
