Reading clocks
A clock face has 12 numbers around it, three hands, and tells a fresh story every minute. Once you know how the hands move, you can read any clock at a glance.
What is this?
The short hand is the hour hand. It moves slowly , only one full turn every 12 hours.
The long hand is the minute hand. It moves faster , one full turn every hour.
The thinnest hand (if there is one) is the seconds hand. It moves the fastest , one full turn every minute.
To read the time:
- Look at the hour hand. It points roughly at the current hour.
- Look at the minute hand. Count from the 12 in steps of 5 minutes.
- Say the time as "hour : minute".
For example, if the hour hand points between 3 and 4, and the minute hand points at 6, the time is 3:30 , half past 3.
A.M. and P.M. : The 12-hour clock repeats twice a day. A.M. is from midnight to noon. P.M. is from noon to midnight.
24-hour format removes the A.M./P.M. confusion. It counts hours from 0 to 23.
- 9:00 A.M. = 09:00.
- 12:00 noon = 12:00.
- 3:00 P.M. = 15:00. (Add 12 to P.M. hours.)
- 9:00 P.M. = 21:00.
- 12:00 midnight = 00:00.
Trains, airlines, and government offices use the 24-hour format because it is unambiguous.
Worked examples
Example 1. The hour hand is between 7 and 8, minute hand at 3. Time?
- Hour: 7 (about). Minutes: 3 × 5 = 15.
- Time: 7:15.
Example 2. Convert 4:30 P.M. to 24-hour format.
- 4 + 12 = 16.
- 16:30.
Example 3. Convert 22:15 to 12-hour format.
- 22 − 12 = 10.
- 10:15 P.M.
Try it
- The hour hand is just past 9. Minute hand at 12. Time?
- Convert 6:45 A.M. to 24-hour format.
- Convert 18:20 to 12-hour format.
- What time is "quarter past 10"?
- What time is "half past 8 in the evening" in 24-hour format?
Hands-on
Clock match. Look at a wall clock. Write down the time in both 12-hour and 24-hour formats. Try this every hour for a day.
Train timetable. Find any train or bus timetable (printed or online). Pick three departure times. Convert each to 12-hour format with A.M./P.M.