GreenBeam Ltd. claims that its compact fluorescent bulbs average no more than 3.55 mg of mercury. A sample of 40 bulbs shows a mean of 3.62 mg of mercury.
 
(a) State the hypotheses for a right-tailed test, using GreenBeam’s claim as the null hypothesis about the mean.
 

1. H₀: μ ≥ 3.55 mg vs. H₁: μ < 3.55 mg
2. H₀: μ ≤ 3.55 mg vs. H₁: μ > 3.55 mg
3. H₀: μ = 3.55 mg vs. H₁: μ ≠ 3.55 mg

multiple choice 1

• a

• b

• c

 

(b) Assuming a known standard deviation of 0.23 mg, calculate the z test statistic to test the manufacturer’s claim. (Round your answer to 2 decimal places.)

 

Test statistic            

 

(c) At the 1 percent level of significance (α = .01) does the sample exceed the manufacturer’s claim?

 

multiple choice 2

• No

• Yes

 

(d) Find the p-value. (Round intermediate calculations to 2 decimal places. Round your answer to 4 decimal places.)

 

p-value