Question

The Inka Kola Soda Company has heard cmp1aints that the amount of soda in their 12-oz. cans is less than 12 ounces. A random sample of 36 12-oz soda cans is taken, resulting in a sample mean of 11.85 oz and a sample standard deviation of s = .18 oz. Assuming that the population is normal, a 95% confidence interval for the true mean amount of soda in a 12-oz can will be:_______

a. 11.85 plus or minus 0.0494
b. 11.85 plus or minus 0.0588
c. 11.85 plus or minus 0.0609
d. 11.85 plus or minus 0.0784

Answer 1

b. 11.85 plus or minus 0.0588

Explanation:

Give the following :

Sample mean (m) = 11.85 oz

Sample standard deviation (s) = 0.18

Confidence interval = 95%

Number of observations (n) = 36

Using the formula:

Mean ± Z95% × (sd/√n)

Z score at 95% confidence interval = 1.96

11.85 ± [1.96 × (0.18/√36)]

11.85 ± [1.96 × (0.18 / 6)]

11.85 ± (1.96 × 0.03)

11.85 ± 0.0588