Question

In: Statistics and Probability

A smoke-detector system uses two devices, A and B. If smoke is present, the probability that...

A smoke-detector system uses two devices, A and B. If smoke is present, the probability that it will be detected by device A is 0.95; by device B is 0.98; and both devices, 0.94. Suppose smoke is present in a home that has the above smoke-detector system installed

What is the probability that the smoke will be detected by only one device?

Solutions

Expert Solution

Let A be the event that smoke is detected by device A and B be the event that smoke is detected by device B

P(A) = 0.95

P(B) = 0.98

P(A B) = 0.94

P(smoke will be detected by only one device) = P(smoke will be detected by A but not by B) + P(smoke will be detected by B but not by A)

= P(A B') + P(B A')

= [P(A) - P(AB)] + [P(B) - P(A B)]

= (0.95 - 0.94) + (0.98 - 0.94)

= 0.01 + 0.04

= 0.05


Related Solutions

A smoke – detector system uses two devices, A and B, which operate independently. When the...
A smoke – detector system uses two devices, A and B, which operate independently. When the smoke is present, the probability that it will be detected by device A is 0.96, the probability that it will be detected by device B is 0.92. a. When the smoke is present, probability that it will be detected by both devices is ________ b. When the smoke is present, probability that it will be detected by at least one device is ________ c....
A house security system uses two devices, A and B. If an emergency happens, the probability...
A house security system uses two devices, A and B. If an emergency happens, the probability that it will be detected by device A is 0.78; and by device B, 0.86; and by either device A or device B or both, 0.96. Determine the probability that an emergency will be detected by device A given that it is detected by device A. Write your answer in percent with 2 decimal places.
In March 1976, plaintiff Albin Laaperi purchased a smoke detector from Sears. The detector, manufactured by...
In March 1976, plaintiff Albin Laaperi purchased a smoke detector from Sears. The detector, manufactured by the Pittway Corporation, was designed to be powered by AC (electrical) current. Laaperi installed the detector himself in one of the two upstairs bedrooms in his home. Early in the morning of December 27, 1976, a fire broke out in the Laaperi home. The three boys in one of the upstairs bedrooms were killed in the blaze. Laaperi’s 13-year-old daughter Janet, who was sleeping...
ABC smoke detector manufacturer claims their smoke detectors can last with average of 105 months and...
ABC smoke detector manufacturer claims their smoke detectors can last with average of 105 months and standard deviation is 10 months. A consumer agency wants to test if the smoke detectors cannot last 105 months. A sample of 36 smoke detectors were tested with the mean of 100 months. Use the 5 percent level of significance, can the consumer agency proof the smoke detectors cannot last 105 mouths
A smoke detector consists of three components with reliabilities of 0.995, 0.994, and 0.996.
A smoke detector consists of three components with reliabilities of 0.995, 0.994, and 0.996. a.         What is the reliability of the system? b.         If identical backups are provided for each component, what is the reliability of the new system? Assume switch reliabilities of 1.0. c.         What is the reliability of the system in part b if the switch reliabilities are 0.998?
Suppose that the failure rate (failing to detect smoke when smoke is present) for a brand...
Suppose that the failure rate (failing to detect smoke when smoke is present) for a brand of smoke detector is 1 in 2000. For safety, two of these smoke detector are installed in a laboratory. (a) What is the probability that smoke is not detected in the laboratory when smoke is present in the laboratory? (b) What is probability that both detectors sound an alarm when smoke is present in the laboratory? (c) What is the probability that one of...
An ordinance requiring that a smoke detector be installed in all previously constructed houses has been...
An ordinance requiring that a smoke detector be installed in all previously constructed houses has been in effect in a particular city for 1 year. The fire department is concerned that many houses remain without detectors. Let p= the true proportion of such houses having detectors and suppose that a portion of random sample of 25 homes is inspected. If the sample strongly indicates that fewer than 80% of all houses have a detector, the fire department will campaign for...
Englewood Company has an opportunity to produce and sell a revolutionary new smoke detector for homes....
Englewood Company has an opportunity to produce and sell a revolutionary new smoke detector for homes. To determine whether this would be a profitable venture, the company has gathered the following data on probable costs and market potential: New equipment would have to be acquired to produce the smoke detector. The equipment would cost $100,000 and be useable for 12 years. After 12 years, it would have a salvage value equal to 10% of the original cost. Production and sales...
Englewood Company has an opportunity to produce and sell a revolutionary new smoke detector for homes....
Englewood Company has an opportunity to produce and sell a revolutionary new smoke detector for homes. To determine whether this would be a profitable venture, the company has gathered the following data on probable costs and market potential: New equipment would have to be acquired to produce the smoke detector. The equipment would cost $100,000 and be useable for 12 years. After 12 years, it would have a salvage value equal to 10% of the original cost. Production and sales...
Englewood Company has an opportunity to produce and sell a revolutionary new smoke detector for homes....
Englewood Company has an opportunity to produce and sell a revolutionary new smoke detector for homes. To determine whether this would be a profitable venture, the company has gathered the following data on probable costs and market potential: New equipment would have to be acquired to produce the smoke detector. The equipment would cost $100,000 and be useable for 12 years. After 12 years, it would have a salvage value equal to 10% of the original cost. Production and sales...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT