Today, in the morning, while going to college, I looked at the clock in the mirror. The clock has no number indication and I made a mistake in interpreting the time (mirror-image). Assuming that the clock must be out of order, I went to college, where I arrive after twenty minutes. At that moment the clock at college shows a time that is two and a half hours later than the time that I saw on the clock (mirror-image) at home.
At what time did I reach college?