Question

An appliance manufacturer claims to have developed a compact microwave oven that consumes a mean of no more than 250 W. From previous studies, it is believed that power consumption for microwave ovens is normally distributed with a population standard deviation of 15 W. A consumer group has decided to try to discover if the claim appears true. They take a sample of 20 microwave ovens and find that they consume a mean of 257.3 W. For a test with a level of significance of 0.01, the critical value would be_. 1) 2.58 2) 1.96 3) 2.5395 4) 1.645

Answer 1

DATE Given that: n=20 X-257.3 To test the hepoth eti e& is 시 2.STD The Cnbcal Valiuen 20.01-12.58 | nsuo er is (1)