Question

A fast food restaurant estimates that the mean sodium content in one of its breakfast sandwiches is no more than 923 milligrams. A random sample of 57 breakfast sandwiches has a mean sodium content of 917 milligrams. Assume the population standard deviation is 24 milligrams. At alpha equals=0.01 do you have enough evidence to reject the​ restaurant's claim? Complete parts​ (a) through​ (e).

Answer 1

Below are the null and alternative Hypothesis,
Null Hypothesis, H0: μ = 923
Alternative Hypothesis, Ha: μ < 923

Rejection Region
This is left tailed test, for α = 0.01
Critical value of z is -2.326.
Hence reject H0 if z < -2.326

Test statistic,
z = (xbar - mu)/(sigma/sqrt(n))
z = (917 - 923)/(24/sqrt(57))
z = -1.89

P-value Approach
P-value = 0.0294
As P-value >= 0.01, fail to reject null hypothesis.

There is not sufficient evidence to conclude that the mean sodium content in one of its breakfast sandwiches is no more than 923 milligrams