Telling the time · Grade 4
In Grade 4 you learn: the 24-hour clock and time intervals.
We tell the time with analogue clocks (with hands) and digital clocks, and we plan our days with hours, minutes, days and months. Working out how long something takes — a film, a journey, a lesson — is one of the most useful bits of maths there is.
Key facts
- 24-hour clock: after midday add 12 to the hour (3:15 pm = 15:15). 00:00 is midnight.
- To find how long something takes, count on to the next o’clock, then on to the end time.
Worked examples
Example 1
Write 19:45 as a 12-hour time.
Answer: 7:45 pm