Work through the levels in order. Type your answer and press Check — open the worked solution if you get stuck. Answers like -6, 3/4 or 0.25 are typed exactly as shown. A ⭐ Bonus Challenge at the end is extra credit — skip it if the rest was hard work.
Level 1 · Warm-up
1 What is 7:40 pm in 24-hour time?
Show worked solution
7 + 12 = 19, so 19:40.
2 A lesson runs from 09:50 to 12:20. Write the minutes from 09:50 to 10:00, and the total length in minutes.
Show worked solution
10 minutes to 10:00, then 2 hours and 20 minutes more: 10 + 120 + 20 = 150 minutes.
3 How many minutes are there in 2 hours 30 minutes?
Show worked solution
2 × 60 + 30 = 150.
Level 2 · Core
4 A shop is open from 23:15 until 00:30. How long is that?
Show worked solution
23:15 to midnight is 45 minutes, and midnight to 00:30 is 30 minutes, giving 1 hour 15 minutes.
5 A train leaves at 16:50 and the journey takes 2 hours 20 minutes. Write the hour it arrives and the minutes past that hour.
Show worked solution
16:50 + 2 hours = 18:50. Then 50 + 20 = 70 minutes = 1 hour 10, so it arrives at 19:10.
6 An event runs from 23:30 to 01:15. How many minutes is that?
Show worked solution
30 + 75 = 105 minutes.
Level 3 · Challenge
7 A download runs from 22:40 to 01:10 and uses 3 gigabytes every hour.1 It lasts 150 minutes.
2 It lasts 2.5 hours.
3 It uses 7.5 gigabytes.
Which statements are correct?
2 It lasts 2.5 hours.
3 It uses 7.5 gigabytes.
Which statements are correct?
Show worked solution
80 + 70 = 150 minutes (1 ✓), which is 2.5 hours (2 ✓). At 3 GB an hour, 2.5 × 3 = 7.5 GB (3 ✓). All three: 1, 2 and 3.
8 A flight leaves at 21:55 and lasts 5 hours 40 minutes. Write the arrival hour (24-hour) and the minutes past that hour.
Show worked solution
21:55 + 5 hours = 02:55 the next day. Then 55 + 40 = 95 minutes = 1 hour 35, so arrival is 3:35.
9 An event lasts from 23:10 to 02:40, and uses 4 gigabytes of data per hour. How many gigabytes is that altogether?
Show worked solution
50 + 160 = 210 minutes = 3.5 hours, and 3.5 × 4 = 14 gigabytes.