In a particular city, the average annual salary for secretaries is $31,000. A sample of 45 secretaries from Company A shows an average annual salary of $27,500 with a population standard deviation of $5,500. Secretaries at Company A claim they are paid less than the city average. What is the test value for this claim?
A) -4.27
B) -0.64
C) 0.64
D) 4.27

Question

Quizplus · Accepted Answer

The test value for this claim can be found using the formula: 
t = (sample mean - population mean) / (population standard deviation / sqrt(sample size))
Plugging in the given values, we get:
t = (27,500 - 31,000) / (5,500 / sqrt(45))
t = -3,500 / 819.42
t = -4.27 (rounded to two decimal places)
Therefore, the test value for this claim is -4.27, so the best choice is (A).

In a Particular City, the Average Annual Salary for Secretaries