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Two cold tablets are unintentionally put in a box containing three aspirin tablets,
that appear to be identical. One tablet is selected at random from the box and swallowed
by the first patient. The second patient selects another tablet at random and swallows it.
Find the probability of event A, that the first patient swallowed a cold tablet.
P(A) =
Find the probability of event B, that exactly one of the two patients swallowed a cold tablet.
P(B) =
Find the probability of event C, that neither patient swallowed a cold tablet.
P(C) =
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P(A) = .
P(B) = + = = = .
The addend is the probability that first patient randomly took one of the two cold tablets,
while the second patient took randomly one of the three aspirin tablets.
The addend is the probability that first patient took randomly one of the three aspirin tablets,
while the second patient took randomly one of the two cold tablets.
P(C) = = = .
First patient took randomly one of the three aspirin tablets from the set of 5 tablets,
and second patient took randomly one of the two remaining aspirin tablets from the set of remaining 4 tablets.
Solved, with complete explanations.