1. A senior high school student has published figures on the number of Kilowatt hours used annually by various home appliances for his research. He claimed that the blender uses an average of 46 kilowatt hours per year. If a random sample of 12 homes included in a planned. Study indicates that blenders use an average of 42 kilowatt hours per year with a standard deviation of 11.9 kilowatt hours, does this suggest at the 0.05 level of significance that blender use, an average, less than 46 kilowatt hours annually? Assume the population of kilowatt hours to be normal.2. A random sample of 100 recorded crocodile deaths in four crocodile farms in Visayas and Mindanao during the past year showed an average life span of 71.8 years. Assuming a population standard deviation of 8.9 years, does this seem to indicate that the mean life span of crocodile in captivity is greater than 70 years? Use a 0.05 level of significance.3. A manufacturer claims that his tires last at least 40,000 miles. A test on 25 tires reveals that the mean life of a tire is 39,750 miles, With a standard deviation of 387 miles. Test the Manufacturer's claim at a = 0.01.4. The Dean of college wants to use the proportion of a population to determine the sample size needed to interview regarding their thoughts about the new school structure. She wants to be able to assert with a probability 0.95 that her error will be at most 0.05. Similar polls in the past showed that 65% approved the new structure.

CLAIM: Ho H1 Level of significance III Type of test IV Critical Region V Test Statistic VI DECISION VII CONCLUSION