Find a duration
From 09:35 to 10:20 is 45 minutes.
Count to the next hour, then add the remaining minutes.
Year 5
Solve problems involving converting between units of time and using timetables
Solve practical time problems using unit conversion and timetable reasoning.
Lesson overview
Time
Time problems often need more than one step. We may need to convert units, work out a duration, or read a timetable carefully before deciding on the calculation.
Use a timetable
If a train leaves at 14:10 and arrives at 15:25, the journey lasts 1 hour 15 minutes.
Read both times accurately before subtracting.
Convert before solving
90 minutes is 1 hour 30 minutes.
A conversion can make the problem easier to read.
Worked example
A film starts at 18:40 and ends at 20:15. How long does it last?
- Count from 18:40 to 19:00, which is 20 minutes.
- Count from 19:00 to 20:00, which is 1 hour.
- Count from 20:00 to 20:15, which is 15 minutes.
- The total duration is 1 hour 35 minutes.
Round 1: Learn it
Read each time carefully, then decide whether you need a conversion or a duration.
Finish this round to unlock Round 2: Show you know it.
Question 1
How long is it from 09:35 to 10:20?
Question 2
A train leaves at 14:10 and arrives at 15:25. How long is the journey?
Question 3
What is 90 minutes as hours and minutes?
Question 4
A film runs from 18:40 to 20:15. How many minutes long is it?
Question 5
Which is later?
Common mistakes
Watch for these as you work through the lesson.
- Subtracting times as if they were ordinary numbers.
- Ignoring the conversion between minutes and hours.
- Reading a timetable entry incorrectly.
Related topics
These ideas connect closely to this lesson.
- Convert between different units of time.
- Use all four operations to solve problems involving measure using decimal notation, including scaling.