Each of 500 soldiers in an army company independently has a certain disease with probability 1 10 3 . This disease will show up in a blood test, and to facilitate matters, blood samples from all 500 soldiers are pooled and tested, a. What is the (approximate) probability that the blood test will be positive (that is, at least one person has the disease)? Suppose now that the blood test yields a positive result. b. What is the probability, under this circumstance, that more than one person has the disease? Now, suppose one of the 500 people is Jones, who knows that he has the disease. c. What does Jones think is the probability that more than one person has the disease? Because the pooled test was positive, the authorities have decided to test each individual separately. The first i -1 of these tests were negative, and the with one—which was on Jones—was positive. d. Given the preceding scenario, what is the probability, as a function of i, that any of the remaining people have the disease?
Each of 500 soldiers in an army company independently has a certain disease with probability 1 10 3 . This disease will show up in a blood test, and to facilitate matters, blood samples from all 500 soldiers are pooled and tested, a. What is the (approximate) probability that the blood test will be positive (that is, at least one person has the disease)? Suppose now that the blood test yields a positive result. b. What is the probability, under this circumstance, that more than one person has the disease? Now, suppose one of the 500 people is Jones, who knows that he has the disease. c. What does Jones think is the probability that more than one person has the disease? Because the pooled test was positive, the authorities have decided to test each individual separately. The first i -1 of these tests were negative, and the with one—which was on Jones—was positive. d. Given the preceding scenario, what is the probability, as a function of i, that any of the remaining people have the disease?
Solution Summary: The author calculates the probability that the blood test will be positive. Each of 500 soldiers in an army company has a certain disease with probability 1/103.
Each of 500 soldiers in an army company independently has a certain disease with probability
1
10
3
. This disease will show up in a blood test, and to facilitate matters, blood samples from all 500 soldiers are pooled and tested, a. What is the (approximate) probability that the blood test will be positive (that is, at least one person has the disease)? Suppose now that the blood test yields a positive result.
b. What is the probability, under this circumstance, that more than one person has the disease? Now, suppose one of the 500 people is Jones, who knows that he has the disease.
c. What does Jones think is the probability that more than one person has the disease? Because the pooled test was positive, the authorities have decided to test each individual separately. The first i -1 of these tests were negative, and the with one—which was on Jones—was positive.
d. Given the preceding scenario, what is the probability, as a function of i, that any of the remaining people have the disease?
A mechatronic assembly is subjected to a final functional test. Suppose that defects occur at random in these
assemblies, and that defects occur according to a Poisson distribution with parameter >= 0.02.
(a) What is the probability that an assembly will have exactly one defect?
(b) What is the probability that an assembly will have one or more defects?
(c) Suppose that you improve the process so that the occurrence rate of defects is cut in half to λ = 0.01.
What effect does this have on the probability that an assembly will have one or more defects?
A random sample of 50 units is drawn from a production process every half hour. The fraction of non-conforming
product manufactured is 0.02. What is the probability that p < 0.04 if the fraction non-conforming really is
0.02?
A textbook has 500 pages on which typographical errors could occur. Suppose that there are exactly 10 such
errors randomly located on those pages. Find the probability that a random selection of 50 pages will contain
no errors. Find the probability that 50 randomly selected pages will contain at least two errors.
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, probability and related others by exploring similar questions and additional content below.