1 2 Suppose the probability of remaining with a particular c

1)

2)

Suppose the probability of remaining with a particular company 10 years or longer is 1/9. A man and a woman start work at the company on the same day. (Enter answers as fractions.) (a) What is the probability that the man will work there less than 10 years? (b) What is the probability that both the man and the woman will work there less than 10 years? (Assume they are unrelated and their lengths of service are independent of each other.) (c) What is the probability that one or the other or both wll work 10 years or longer? (c) What is the probability that one or the other or both will work 10 years or longer?

Solution

(1) (a) 1-1/9=8/9

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(b) (8/9)*(8/9)=64/81

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(c) (1/9)+(1/9)-(1/9)*(1/9) =2/9 + 1/81

=(18+1)/81

=19/81

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(2)(a)The probability that the wife has type A blood and the husband has type B blood is

0.39*0.1 = 0.039

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(b)

The probability that one member of the couple has type A blood and the other member of the couple has type B blood is

0.39*0.1= 0.039