Hurley and Locke both want to get a haircut at the Dharma Hair Salon, and both can only arrive at the salon between 2:30 pm and 4:00 pm. Each haircut takes exactly 30 minutes. Assume that the salon can give haircuts to as many people as necessary simultaneously, there is no waiting time, and customers leave immediately after their haircuts are over. If Hurley and Locke both go to the Dharma Hair Salon on the same day, what is the probability that they will see each other there?

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