Sometime during every hour the minute hand lies directly above the hour hand.

During the twelve hours of the day the hands are together exactly 11 times. This means that they are together at 12 o'clock and every 1 hour and 5$\frac{5}{11}$ minutes afterwards. Extending this to between 4 o'clock and 5 o'clock the hands must be together at 21 and $\frac{9}{11}$ minutes past 4 o'clock or (putting that another way) 4:21:49 and $\frac{1}{11}$ of a second.