Question

Radon is a colorless, odorless gas that is naturally released by rocks and soils and may concentrate in tightly closed houses. Since radon is slightly radioactive, there is some concern that it may be a health hazard. Radon detectors are sold to homeowners worried about this risk, but the detectors may be inaccurate. University researchers placed 30 radon detectors in a chamber where they were exposed to 105 picocuries per liter (pCi/l) of radon over 3 days. The sample average reading from the 30 radon detectors was 103.03 pCi/l and the sample standard deviation was 5.1 pCi/l. Are the researchers able to conclude at the 5% significance level that the average reading differs from the true value of 105?

1. To test: H_o: (Click to select)μαβx¯ (Click to select)≠><=≤≥   vs. H_a: (Click to select) x¯μ β α (Click to select)><=≥≤≠

2. Test Statistic (Round to 3 decimals): t =

3. p-value (Round to 3 decimals):

Conclusion: At α = , (Click to select)reject Hado not reject Hareject Hodo not reject Ho since p-value (Click to select)><= α. We have (Click to select)sufficientinsufficient evidence to conclude that the (Click to select)population standard deviationpopulation averagesample averagesample standard deviationreading (Click to select)is less thanis greater thanis equal todiffers from .

Answer 1