Question

scientists want to estimate the mean weight of mice after they have been fed a special diet period from previous studies that is known that the weight is normally distributed with standard deviation 6 grams. How many mice must be weighed so that 95% confidence interval will have a margin error of 0.5 grams ? Right only an integer as your answer

Answer 1

Solution :

Given that,

Population standard deviation = = 6

Margin of error = E = 0.5

At 95% confidence level the z is,

= 1 - 95%

= 1 - 0.95 = 0.05

/2 = 0.025

Z_/2 = 1.96

sample size = n = [Z_/2* / E] ²

n = [1.96 * 6 / 0.5]²

n = 553.19

Sample size = n = 554