A manufacturer of a chemical used in glue, attempting to control the amount of a hazardous chemical its workers are exposed to, has given instructions to halt production if the mean amount in the air exceeds 3.0ppm. A random sample of 50 air specimens produced the following statistics: sample mean = 3.1 ppm, sample standard deviation = 0.5 ppm. Assume measurements are normally distributed.
-The appropriate test statistic to test the hypotheses is _____.
A)1.00
B)-1.00
C)2.80
D)1.41
E)-1.41

Question

Quizplus · Accepted Answer

The appropriate test statistic to test the hypotheses is the t-statistic given by:
t = (x̄ - μ) / [s / sqrt(n)]
where x̄ is the sample mean, μ is the hypothesized population mean, s is the sample standard deviation, and n is the sample size.

Plugging in the values, we get:
t = (24-20) / [14 / sqrt(25)] = 1.41

Therefore, the best choice is D, 1.41.

A Manufacturer of a Chemical Used in Glue, Attempting to Control