Statistics

topic: computing for test statistics for population mean

Let's Practice For each problem indicated below, do the following: A. Formulate the decision rule. B. Compute for the appropriate test statistics. C. Draw conclusion based on the decision rule and the test statistics. 1. A researcher claims that the yearly consumption of soft drinks per person is 52 gallons. In a sample of 50 randomly selected people, the mean of the yearly consumption was 56.3 gallons. The standard deviation of the population is 3.5 gallons. Use a = 5%. 2. A health researcher read that a 200-pound male can burn an average of 546 calories per hour playing tennis. Thirty six males were randomly selected and tested. The mean of the number of calories burned per hour was 544.8. Test the claim that the average number of calories burned is actually less than 546, and find the P-value. On the basis of the P-value, should the null hypothesis be rejected at a = 0.01? The standard deviation of the population is 3. 3. The average undergraduate cost for tuition, fees, room, and board for all institutions last year was Php26,025. A random sample of 40 institutions of higher learning this year indicated that the mean tuition, fees, room, and board for the sample was Php27,690, and the population standard deviation is Ph5,492. At the 0.05 level of significance, is there sufficient evidence that the cost has increased? 4. The breaking strengths of cables produced by a manufacturer have mean 1800 lbs. and standard deviation 100 lbs. By a new technique in the manufacturing process it is claimed that the breaking strength can be increased. To test this claim, a sample of 50 cables is tested, and it is found that the mean breaking strength is 1850 1b. 5. An educator claims that the average salary of substitute teachers in schools in a certain province, is less than Php800 per day. A random sample of eight schools is selected, and the daily salaries (Php) are shown. Is there enough evidence to support the educator's claim at a = 0.10? 600 560 600 550 700 550 600 850 900