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This problem happened to me almost 3 years ago and I just discovered this site by luck, so I want some help to know if this problem is solvable (if so, I would like to know how to solve it as well as the probabilities for each question) or if it cannot be solved due to lack of information.

The problem of my friend

I found my friend at university at the beginning of the 10 first days of January, February and March: January 10, February 10 and March 2.

  1. What was the probability to meet at least 1 time this friend during the first 10 days for each month? (February had 28 days in 2011)

  2. What would have been the probability to meet this friend at least 1 time for each month during the non-first 10 days?

  3. What would have been the probability to meet this friend more than 1 time during the first 10 days of each month?

Because February had 28 days in 2011, would it be correct to say the following:

"It would have been more probable to meet this friend during the non-first 10 days of February than during the non-first 10 days of March?

As one more fact, I met this friend twice in March on Tuesday 15 and Friday 18.

I hope anyone can help me to solve this peculiar problem that really happened to me and got my attention since then. Thank you very much for your time and help :)

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