Question

An experimenter is interested in estimating the dairy intake for males in a population. She took a random sample of 100 males and found the sample mean to be 755 grams per day and standard deviation to be 30 grams. . Round your solution to two significant digits after decimal.

1. a. Compute a 95% confidence interval for the mean gram intake of dairy products for males in the population. (8 points)
2. b. Interpret the confidence interval obtained in part a. (2 points)

Answer 1

a)

= 755, s = 30, n = 100

95% confidence interval for mean is given by.

z = 1.96

- z*s /Sqrt(n) < < + z*s /Sqrt(n)

755 -1.96 *30/sqrt(100) < < 755 +1.96 *30/sqrt(100)

755 - 5.88 < < 755 + 5.88

749.12 < < 760.88

95% confidence interval for

b) we are  95% confident for the mean gram intake of dairy products for males in the population is between 749.12 to 760.88