Question

You are interested in estimating the the mean weight of the local adult population of female white-tailed deer (doe). From past data, you estimate that the standard deviation of all adult female white-tailed deer in this region to be 39 pounds. What sample size would you need to in order to estimate the mean weight of all female white-tailed deer, with a 98% confidence level, to within 5 pounds of the actual weight? (Use Excel to find the appropriate critical value and round to 3 decimal places.)

Answer 1

Given that, population standard deviation = 39 pounds

margin of error (E) = 5 pounds

=> Significance level = 1 - 0.98 = 0.02

Using Excel we get, critical value at significance level of 0.02 is,

Excel Command : =NORMSINV (0.02/2) = 2.326

We want to find, the sample size (n),

Therefore, required sample size is 330

Note : if you want, sample size is to nearest whole number then, n = 329