A random sample of 150 recent donations at a certain blood bank reveals that 82 are type A blood. Does this suggest that the actual percentage of type A donations differs from 40%, the percentage of the population having type A blood? Carry out a test of the appropriate hypotheses using a significance level of .01. Would your conclusion have been different if a significance level of .05 had been used? A plan for an executive travelers' club has been developed by an airline on the premise that 5% of its current customers would qualify for membership. A random sample of 300 customers yielded 40 who would qualify. a) Using this data, test at level .01 the null hypothesis that the company's premise is correct against the alternative that it is not correct. b) What is the probability that when the test of part (a) is used, the company's premise will be judged correct when in fact 10% of all current customers qualify? Suppose the average weight of the residents of town ABC is 160 lbs. A nutritionist believes that the true average weight is different based on his experience. He measured the weight of 45 individuals and found the mean to be 165 lbs with a standard deviation of 3.6. a) At a 90% confidence level, is there enough evidence to reject the null hypothesis? (use the p-value method) b) At a 95% confidence level, is there enough evidence to reject the null hypothesis? (use the p-value method) A random sample of 55 smoke detectors yielded an average of 4.10 mg of americium-241 (a radioactive material) with a standard deviation of .21 mg. With a significance level of .05, do we have compelling evidence that the population mean of americium-241 is 4.00 mg per smoke detector? . The recommended daily dietary allowance for zinc among males older than age 50 years is 15 mg/day. The article "Nutrient Intakes and Dietary Patterns of Older Americans: A National Study" (J. of Gerontology, 1992: M145-150) reports the following summary data on intake for a sample of males aged 65-74 years: n = 115, X = 11.3 and S = 6.43. Does this data indicate that the average daily zinc intake in the population of all males ages 65-74 falls below the recommended allowance?