The probability of the Bob arrived before 1.30 P.M is 1/2 if the Alice arrives after Bob.
According to the question,
Alice and Bob each arrive at a party at a random time between 1.00 P.M and 2.00 P.M.
In probability theory, the sample space(s) of a random trial is the set all possible results of that trial.
Let 'x' be the arrival time of Alice and 'y' be the arrival time of Bob.
s = {(x, y) /1≤x≤2 and 1≤y≤2}
In order to find the probability of the Bob arrived before 1.30 P.M, if the Alice arrives after Bob.
Formula for Probability = [tex]\frac{Number of favorable events}{Total number of events}[/tex]
= 1/2
Hence, the probability of the Bob arrived before 1.30 P.M is 1/2 if the Alice arrives after Bob.
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