GreenBeam Limited claims that its compact fluorescent bulbs average no more than 3.24 mg of mercury. A sample of 25 bulbs shows a mean of 3.29 mg of mercury. Required:
a. State the hypotheses for a right-tailed test, using GreenBeam’s claim as the null hypothesis about the mean.
b. Assuming a known standard deviation of 0.21 mg, calculate the z test statistic to test the manufacturer’s claim.
c. At the 1 percent level of significance (α = 0.01) does the sample exceed the manufacturer’s claim?
d. Find the p-value.