Probability of a train and a bus will meet Would you explain the answer of the question in terms of independent events or other basic concepts in probability?

(Q) A train and a bus arrive at the station at random between 9 am and 10 am. The train stops for 10 minutes and the bus for x minutes. Find x so that the probability that the bus and the train will meet equals 0.5.

Many thanks in advance!
For any time the train arrives, the bus will meet it if it arrives between x minutes before the train arrives and 10 minutes after that.  That is a window of opportunity of $10+x$ minutes in the $60$ minute frame.  Find the $x$ that gives the required probability.
For any time the train arrives, the bus will meet it if it arrives between x minutes before the train arrives and 10 minutes after that.  That is a window of opportunity of $10+x$ minutes in the $60$ minute frame.  Find the $x$ that gives the required probability.