How many times during a 12 hour period does the hour hand and the minute hand of the clock cross each other?
Answer:
11
- The minute hand makes one full revolution every one hour. Therefore, it will make 12 revolutions in a period of 12 hours.
- During each revolution, the minute hand crosses the hour hand once. Therefore, if the hour hand remains fixed, it would cross the hour hand 12 times.
- But the hour hand does not remain fixed and makes one full revolution in 12 hours. This means, the total numbers of crossings made by the minute hand will be 1 less than the number of revolutions made by it. Therefore, the total numbers of crossings will be 11.
- For example, if we start at 12 midnight, the two hands will meet at: (approximately)
12 AM
1:05 AM
2:10 AM
3:16 AM
4:22 AM
5:27 AM
6:33 AM
7:38 AM
8:43 AM
9:48 AM
10:54 AM