SOLUTION: Suppose that after 10 years of service, 30% of computers have problems with motherboards (MB), 20% have problems with hard drives (HD), and 15% have problems with both MB and HD. W

Algebra ->  Probability-and-statistics -> SOLUTION: Suppose that after 10 years of service, 30% of computers have problems with motherboards (MB), 20% have problems with hard drives (HD), and 15% have problems with both MB and HD. W      Log On


   

Question 1164589: Suppose that after 10 years of service, 30% of computers have problems with motherboards (MB), 20% have problems with hard drives (HD), and 15% have problems with both MB and HD. What is the probability that a 10-year old computer still has fully functioning MB and HD? (10)
Answer by ikleyn(52886) About Me  (Show Source):
You can put this solution on YOUR website!
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    P(MB or HD) = P(MB) + P(HD) - P(both) = 0.3 + 0.2 - 0.15 = 0.35.


    P(a 10-years old computer is OK) = 1 - 0.35 = 0.65 = 65%.    ANSWER

Solved.