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Worksheet

Extension & Challenge — Measurement & Time

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Part A — Reading Clocks & 24-Hour Time

The same moment can be written two ways. 12-hour time uses am and pm; 24-hour time counts straight through to 23:59. After midday, add 12 to the hour: 1 pm becomes 13:00.

Three analog clock faces labelled A, B and C showing 3:15, 9:40 and 7:05.
Clocks A, B and C. Read the hour and minute hands carefully.
1 Write the time shown on each clock, then write it in 24-hour time as if it were in the afternoon/evening.

A:

B:

C:

2 How much time passes from the time on clock A to the time on clock C (same afternoon)?
3 A film starts at the time on clock B and lasts 1 hour 45 minutes. What time does it finish?

Answer:

4 Complete these conversions.

(a) 90 minutes = hours minutes

(b) hours = minutes

5 Rewrite each 24-hour time as a 12-hour time with am or pm: 14:30, 06:05, 23:15.
6 Reasoning. Give one real situation where 24-hour time avoids confusion that 12-hour time could cause.

Part B — Elapsed Time & Timetables

Elapsed time is how long passes between a start and an end. A good trick is to count up to the next whole hour first, then add the remaining hours and minutes.

1 A bus leaves at 8:50 am and arrives at 9:35 am. How long is the journey?

Answer:

2 Use the timetable to answer the questions.
StopDeparts
Central09:15
Riverside09:48
Hilltop10:25

(a) How long from Central to Riverside?

(b) How long for the whole trip, Central to Hilltop?

3 A train leaves at 13:20 and the trip takes 2 hours 40 minutes. What time does it arrive (24-hour time)?

Answer:

4 Add these two durations: 1 h 50 min + 2 h 25 min.

Answer:

5 Work backwards. You must arrive by 5:00 pm. The journey takes 1 hour 35 minutes. What is the latest time you can leave?
6 Plan it. You wake at 7:00 am. Breakfast takes 20 min, getting ready 25 min, and the walk to school 15 min. What time do you arrive? How much spare time before the 8:30 am bell?