The Employee Benefit Research Institute reports that 69% of workers reported that they and/or their spouse had saved some money for retirement. If a random sample of 30 workers is taken, what is the probability that fewer than 17 workers and/or their spouses have saved some money for retirement? If a random sample of 50 workers is taken, what is the probability that more than 40 workers and/or their spouses have saved some money for retirement? How the results in (a) & (b) are different from each other?

A study was conducted to determine whether there were significant differences between college students admitted through special programs (such as retention incentive and guaranteed placement programs) and college students admitted through the regular admissions criteria. It was found that the graduation rate was 90.8% for the college students admitted through special programs. If 10 of the students from the special programs are randomly selected, find the probability that at least 9 of them graduated. prob = If 10 of the students from the special programs are randomly selected, find the probability that eactly 7 of them graduated. prob = Would it be unusual to randomly select 10 students from the special programs and get exactly 7 that graduate? Oyes, it is unusual Ono, it is not unusual If 10 of the students from the special programs are randomly selected, find the probability that at most 7 of them graduated. prob = Would it be unusual to randomly select 10 students from the special…

Apparently, depression significantly increases the risk of developing dementia later in lift (BBC News, July 6, 2010). In a recent study it was reported that 22% of those who had depression went on to develop dementia, compared to only 17% of those who did not have depression. Suppose 10% of all people suffer from depression.   What is the probability of a person developing dementia?   If a person has developed dementia, what is the probability that the person suffered from depression earlier in life?

A study was conducted to determine whether there were significant differences between college students admitted through special programs (such as retention incentive and guaranteed placement programs) and college students admitted through the regular admissions criteria. It was found that the graduation rate was 92.3% for the college students admitted through special programs.If 12 of the students from the special programs are randomly selected, find the probability that at least 11 of them graduated.prob = If 12 of the students from the special programs are randomly selected, find the probability that eactly 9 of them graduated.prob =

A certain blood test is 99.5% effective at detecting Foreign Bloodborne Pathogens (such as the hepatitis virus) in human blood. If two people who take this test are selected at random, what is the probability both tests correctly detect a Foreign Bloodborne Pathogen? If ten people who take this test are selected at random, what is the probability all tests correctly detect a Foreign Bloodborne Pathogen? If 1,000 people who take this test are selected at random, what is the probability at least one test FAILS to detect a Foreign Bloodborne Pathogen?

In a study of 213,270 cell phone users, it was found that 77 developed cancer of the brain or nervous system. Assuming that cell phones have no effect, there is a 0.000397 probability of a person developing cancer of the brain or nervous system. We therefore expect about 85 cases of such cancer in a group of 213,270 people. Estimate the probability of 77 or fewer cases of such cancer in a group of 213,270 people. What do these results suggest about media reports that cell phones cause cancer of the brain or nervous system? (a) P(x ≤ 77) = (Round to four decimal places as needed.)