Question

The output voltage for an electric circuit is specified to be 134 volts. A sample of 40 independent readings on the voltage for this circuit gave a sample mean 132.1 volts and standard deviation 2.2 volts. Test the hypothesis that the average output voltage is 134 volts against the alternative that it is less than 134 volts. Use a test with level 0.05.

State the null and alternative hypotheses.

H₀: μ = 134
H_a: μ ≠ 134

H₀: μ = 132.1
H_a: μ < 132.1    

H₀: μ = 132.1
H_a: μ ≠ 132.1

H₀: μ = 134
H_a: μ < 134

H₀: μ = 132.1
H_a: μ > 132.1

State the rejection region. (Round your answers to two decimal places. If the test is one-tailed, enter NONE for the unused region.)

z > ____

z < ____

Calculate the appropriate test statistic. (Round your answer to two decimal places.)

z = ____

What is the conclusion of your test?

Reject H₀. There is not enough evidence to conclude the mean output voltage for this electrical circuit is less than the desired voltage.

Fail to reject H₀. There is not enough evidence to conclude the mean output voltage for this electrical circuit is less than the desired voltage.    

Fail to reject H₀. There is enough evidence to conclude the mean output voltage for this electrical circuit is less than the desired voltage.

Reject H₀. There is enough evidence to conclude the mean output voltage for this electrical circuit is less than the desired voltage.

Answer 1