On a regular 12-hour digital clock how many times would the same three digits in a row be displayed (e.g. 1:11,11:12,12:22) in one day?

18 times ( 9 * 2 ) . 1:11 2:22 3:33 4:44 5:55 10:00 11:10 11:11 12:22

On a 12-hour digital clock, what is the smallest interval between two times that are palindromic (can be read forwards and backwards as the same number)?

On a digital clock there are times which have the special property that the minutes digits add up to the hours digit, like 7:25 or 13:49. Which hour has the most of these times?