Question

Assume that the weights of spawning Chinook salmon in the Columbia river are normally distributed. You randomly catch and weigh 25 such salmon. The mean weight from your sample is 31.2 pounds with a standard deviation of 4.4 pounds. You want to construct a 90% confidence interval for the mean weight of all spawning Chinook salmon in the Columbia River. What is the point estimate for the mean weight of all spawning Chinook salmon in the Columbia River?

Answer 1

Answer: The point estimate for the mean weight of all spawning Chinook salmon in the Columbia River is the mean weight from your sample $(\overline{x})$ = 31.2 pounds .

Step-by-step explanation:

The weights of spawning Chinook salmon in the Columbia river are normally distributed.

Given :  The mean weight from your sample is 31.2 pounds with a standard deviation of 4.4 pounds.

The point estimate for the mean $(\mu)$ weight of all spawning Chinook salmon in the Columbia River is the mean weight from your sample $(\overline{x})$ i.e. is 31.2 pounds because the best point estimate for population mean is the sample mean. [in normal distribution]