A telemarketing company has a special letter-opening machine that opens and removes the contents of an envelope. If the envelope is fed improperly into the machine, the contents of the envelope may not be removed or may be damaged. In this case, the machine is said to have “failed.” (a) If the machine has a probability of failure of 0.01, what is the probability of more than 1 failure occurring in a batch of 20 envelopes? (b) If the probability of failure of the machine is 0.01 and a batch of 500 envelopes is to be opened, what is the probability that more than 8 failures will occur?

Cathy is planning to take the Certified Public Accountant Examination (CPA exam). Records kept by the college of business from which she graduated indicate that 60% of students who graduated pass the CPA exam. Assume that the exam is changed each time it is given. Let n = 1, 2, 3, ... represent the number of times a person takes the CPA exam until the first pass. (Assume the trials are independent.) (a) What is the probability that Cathy passes the CPA on the first try? (Use 2 decimal places.)(b) What is the probability that Cathy passes the CPA exam on the second or third try? (Use 4 decimal places.)

Cathy is planning to take the Certified Public Accountant Examination (CPA exam). Records kept by the college of business from which she graduated indicate that 81% of students who graduated pass the CPA exam. Assume that the exam is changed each time it is given. Let n = 1, 2, 3, ... represent the number of times a person takes the CPA exam until the first pass. (Assume the trials are independent.) (a) What is the probability that Cathy passes the CPA on the first try? (Use 2 decimal places.)(b) What is the probability that Cathy passes the CPA exam on the second or third try? (Use 4 decimal places.)

The state medical school has discovered a new test for tuberculosis. (If the test indicates a person has tuberculosis, the test is positive.) Experimentation has shown that the probability of a positive test is 0.77, given that a person has tuberculosis. The probability is 0.09 that the test registers positive, given that the person does not have tuberculosis. Assume that in the general population, the probability that a person has tuberculosis is 0.04. What is the probability that a person chosen at random will fall in the following categories? (Enter your answers to four decimal places.) have tuberculosis and have a positive testnot have tuberculosisnot have tuberculosis and have a positive test

A laboratory blood test is 99 percent effective in detecting a certain disease when it is, in fact, present. However, the test also yields a "false positive" result for 1 percent of the healthy persons tested. (That is, if a healthy person is tested, then, with probability .01, the test result will imply he or she has the disease.) If .5 percent of the population has the disease, what is the probability that a person has the disease given that his test result is positive?

Given the probability that "she's up all night 'til the sun" OR "she's up all night for good fun" is 0.19, the probability that "she's up all night for good fun" is 0.44, and the probability that "she's up all night 'til the sun" is 0.48, what's the probability that "she's up all night 'til the sun" AND "she's up all night for good fun"?

Cathy is planning to take the Certified Public Accountant Examination (CPA exam). Records kept by the college of business from which she graduated indicate that 75% of students who graduated pass the CPA exam. Assume that the exam is changed each time it is given. Let n = 1, 2, 3, ... represent the number of times a person takes the CPA exam until the first pass. (Assume the trials are independent.) (a) What is the probability that Cathy passes the CPA on the first try? (Use 2 decimal places.)(b) What is the probability that Cathy passes the CPA exam on the second or third try? (Use 4 decimal places.)

During the 1971-72 season, the Los Angeles Lakers won 69 games and lost 13. Assuming that the outcomes of the basketball games are independent and that the percentageof wins this season will be the same as in 1971-1972, answer the following questions: (a) What is the probability that the Lakers will win the first twogames of the season?   (b) What is the probability that the Lakers will win the first sevengames of the season?