You realize that it happens once in the one o'clock hour, once in the two o'clock hour, and so forth.
At midnight, the hour and minute hands of a standard 12-hour wall clock align. You wonder how many times over the course of a day this happens. You realize that it happens once in the one o'clock hour, once in the two o'clock hour, and so forth. Knowing this, and only counting midnight once, how many times a day do the hour and minute hands of an analog clock line up? You have 15 seconds.
At midnight, the hour and minute hands of a standard 12-hour wall clock align.
{22}