Question

A consumer products company is formulating a new shampoo and is interested in foam height (in millimeters). Foam height is approximately normally distributed and has a standard deviation of 20 millimeters. The company wishes to test H0:μ⁢=175 millimeters versus H1:μ⁢>175 millimeters, using the results of n=4 samples. Calculate the P-value if the observed statistic is x¯=180. Round your answer to four decimal places (e.g. 98.7654).

Answer 1

P-value = 0.3085

Explanation:

The null and alternative hypothesis is,

H0 is μ 175

Ha is μ > 175

x’ = 180

σ = 20

n = 4

Test statistic = z = ( x’ - mew) / / √n

= (180 - 175) / 20 / 4

Test statistic = z = 0.50

This is the right tailed test

p(Z > 0.50) = 1-P (Z < 0.50) = 1 - 0.6915

P-value = 0.3085