Showing 11 to 20 of 1246 Questions

The probability that a patient recovers from a delicate heart operation is 0.9. What is the probability that exactly 5 of the next 7 patients having this operation survive?
0194 
A traffic control engineer reports that. 75% of the vehicles passing through a checkpoint are from within the state. What is the probability that fewer than 4 of the next 9 vehicles arc from out of state?
0378 
A study examined national attitudes about antidepressants. The study revealed that approximately 70% believe "antidepressants do not really cure anything they just cover up the real trouble." According to this study, what is the probability that at least 3 of the next 5 people selected at random will be of this opinion?
2256 
It is known that the percentage of wins for the Chicago Bulls basketball team going into the playoffs for the 199697 season was 87.7. Round the 87.7 to 90 in order to use Table A.1(a) What is the probability that the Bulls will sweep (40) in the initial bestof7 playoff series?(b) What is the probability that the Bulls would tain the i
1472 
It is known that 60% of mice inoculated with a serum are protected from a certain disease. If 5 mice are inoculated, find the probability that(a) None contracts the disease;(b) Fewer than 2 contract the disease;(c) More than 3 contract the disease.
0336 
Suppose that airplane engines operate independently and fail with probability equal to 0.4. Assuming that a plane makes a safe flight if at least onehalf of its engines run, determine whether a 4engine plane or a 2engine plane has the higher probability for a successful flight.
0511 
If X represents the number of people in Exercise 5.13 who believe that antidepressants do not cure but only cover up the real problem, find the mean and variance of X when 5 people are selected at random and then use Chebyshev's theorem to interpret the interval μ ± 2a.
0312 
(a) In Exercise 5.9, how many of the 15 trucks would you expect to have blowouts?(b) According to Chebyshev's theorem, there is a probability of at least 3/4 that the number of trucks among the next 15 that have blowouts will fall in what interval?
1559 
As a student drives to school, he encounters a traffic signal. This traffic signal stays green for 35 seconds, yellow for 5 seconds, and red for 60 seconds. Assume that the student goes to school each weekday between 8:00 and 8:30. Let X1 be the number of times he encounters a green light, X2 be the number of times he encounters a yellow
1419 
According to USA Today (March 18, 1997), of 4 million workers in the general workforce, 0.8% tested positive for drugs. Of those testing positive, 22.5% were cocaine users and 54.4% marijuana users.(a) What is the probability that of 10 workers testing positive, 2 are cocaine users, 0 marijuana users, and 3 users of other drugs?(b) What i
2503