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A arrives at office at 8-10am regularly; B arrives at 9-11 am every day. Probability that one day B arrives before A? [Assume arrival time of both A and B are uniformly distributed]
asked | 115 views
there is a 60 min. intersection. what is the answer given?
@Vaishali.

If B comes at 9, A can come at any time after 9

If B comes at 9.01, A can come at any time after 9.01

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If B comes at 9.59, A can come only at 10.

So, favourable events = 59+ 58+........+2+1

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lets consider sample space.

If A arrives at 8, B can arrive anytime between 9-11 i.e. 120 min

If A arrives at 8.01, B can arrive anytime between 9-11 i.e. 120 min

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If A arrives at 10.00, B can arrive anytime between 9-11 i.e. 120 min

THus, sample space = 120 * 120

So, probablity = 1/8 (approx)