Answer:
(a) 3/10
(b) 9/20
Explanation:
In order to answer this question, we must assume the probabilities are independent.
(a) p(both alive) = p(S alive)×p(A alive) = (3/4)(2/5) = 3/10
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(b) p(only S alive) = p(S alive)×p(A not alive) = (3/4)(1 -2/5) = 9/20