SOLVED

11) A system has three components in parallel with reliabilities 0.9, 0.7, and 0.5. What is the system reliability? A) 0.315 B) 0.700 C) 0.900 D) 0.985 E) 2.100 12) Components A, B, and C are connected in series. Component D is connected in parallel to component B. Which of the following statements is true? A) The system works only if A works, B or C works, and D works. B) Component B must work for the system to work. C) The system works when A works, C, works, and either B or D works. D) Components B and C are backups to A. E) The system works if D works, and any of A, B, or C works. 13) A job consists of a series of three tasks. Task 1 is performed correctly 98% of the time, task 2 is performed correctly 99% of the time, and task 3 is performed correctly 97% of the time. What is the reliability of this job? A) 91.27% B) 94.11% C) 97.00% D) 98.00% E) 99.00% A) increases. B) stays the same. C) decreases. D) increases, then decreases. E) decreases, then increases. 15) What is the reliability of the three components connected in series shown below? A) 0.799425 B) 0.85000 C) 0.91333 D) 0.95000 E) 2.79 16) Consider a product with three components in series, with reliabilities of 0.90, 0.80, and 0.99 for components A, B, and C, respectively. Furthermore, component B uses a backup that also has a reliability of 0.80. What is the reliability of the system? A) 0.50000 B) 0.71280 C) 0.80000 D) 0.85536 E) 3.49000 17) Ten high-technology batteries are tested for 200 hours each. One failed at 20 hours; all others completed the test. FR(%) is ________ and MTBF is ________. A) 10%; 1/1820 B) 90%; 1/1820 C) 10%; 1820 hours D) 10%; 1980 hours E) 10%; 2000 hours 18) Ten high-technology batteries are tested for 200 hours each. One failed at 50 hours; all others completed the test. FR(%) is ________ and FR(N) is ________. A) 10%; 1/1850 B) 10%; 1/2000 C) 25%; 1850 hours D) 90%; 1/2000 E) 10%; 1/1950 19) Ten high-technology batteries are tested for 200 hours each. One failed at 20 hours; another failed at 140 hours; all others completed the test. FR(%) is ________ and MTBF is ________. A) 20%; 880 hours B) 10%; 1980 hours C) 20%; 1760 hours D) 20%; 1000 hours E) 80%; 920 hours A) calendar time between failures. B) operating time between failures. C) number of failures per unit time. D) number of operations between failures. E) downtime per breakdown.