Time
Time is a fundamental measurement that quantifies duration and position in the day using standardised units. The basic relationships form a hierarchy: 60 seconds equal 1 minute, 60 minutes equal 1 hour, and 24 hours equal 1 day. These conversions appear throughout the Year 3 National Curriculum when pupils learn to tell and write time to the nearest minute.
Why it matters
Time calculations appear constantly in daily life, from working out bus arrival times to planning cooking schedules. A recipe that needs 1 hour 45 minutes cooking time starting at 16:30 will finish at 18:15. Sports events rely on precise timing: a 90-minute football match starting at 15:00 ends at 16:30. Television programmes use 24-hour scheduling, so understanding that 20:00 equals 8 pm becomes essential. In GCSE mathematics, time problems often involve calculating wages (7.5 hours at £12 per hour equals £90), journey planning, or interpreting timetables. Professional contexts require time skills constantly: nurses calculating medication intervals, engineers timing processes, or shop managers scheduling staff rotas. Even simple tasks like charging a phone (2 hours from 18:00 means ready by 20:00) use these principles daily.
How to solve time
Time
- 60 seconds = 1 minute; 60 minutes = 1 hour; 24 hours = 1 day.
- To convert hours to minutes: multiply by 60.
- Elapsed time: count forward from start to end.
- 24-hour clock: add 12 to pm hours (e.g. 3 pm = 15:00).
Example: 2 h 30 min = 2 × 60 + 30 = 150 minutes.
Worked examples
How many minutes in 1 hour?
Answer: 60
- Recall the time fact → 60 — Think of the minute hand going all the way around the clock once. It passes 60 tiny marks -- one for each minute.
- State the answer clearly → There are 60 minutes in 1 hour — The answer is 60. This is a basic time fact worth memorising, just like knowing there are 10 fingers on your hands.
What time is it 5 hours after 05:00?
Answer: 10:00
- Read the starting time → Start: 05:00 — We begin at 05:00. Think of where the hour hand is pointing on a clock.
- Count 5 hours forward → 5 + 5 = 10 — Add 5 to the hour: 5 + 5 = 10.
- Write the final time → 10:00 — The answer is 10:00. On a 24-hour clock, that's 10:00.
A football match starts at 08:15 and lasts 2 hours 20 minutes. When does it end?
Answer: 10:35
- Read the starting time → Start: 08:15 — The event begins at 08:15. Write down the start hour (8) and start minutes (15) separately.
- Add the hours first → 8:15 + 2h = 10:15 — Adding hours is easy -- just move the hour hand forward by 2. We go from hour 8 to hour 10.
- Add the minutes → 15 + 20 = 35 min — Add 20 minutes to 15: 15 + 20 = 35. This is less than 60, so no carrying needed.
- Combine into final time → 10:35 — The event ends at 10:35. Think of it like this: 08:15 plus 2 hours 20 minutes lands you at 10:35.
Common mistakes
- Confusing 12-hour and 24-hour formats leads to writing 3:00 pm as 3:00 instead of 15:00.
- Adding minutes incorrectly by treating time like decimal numbers, writing 2:30 + 45 minutes as 2:75 instead of 3:15.
- Forgetting to carry when minutes exceed 60, calculating 8:45 + 30 minutes as 8:75 instead of 9:15.
- Mixing up elapsed time direction, finding the time 2 hours before 10:00 as 12:00 instead of 08:00.