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Class 4

Chapter 12: Ticking Clocks and Turning Calendar

Clocks measure time in hours and minutes; calendars measure days, weeks and months. Knowing how to add and subtract time helps us plan.

Learning outcomes

  • Read time to the minute
  • Compute durations across days and months

Activities

  • Plan a 3-day school trip on a calendar

Worked examples

Read through these first, then try the practice below.

  1. Example 1 — Find the duration

    School starts at 8:30 and ends at 2:00. How long is school?

    Solution: From 8:30 to 12:30 is 4 hours; from 12:30 to 2:00 is 1 hour 30 minutes. Total: 5 hours 30 minutes.

  2. Example 2 — Days between dates

    How many days are there from 5 March to 12 March?

    Solution: 12 − 5 = 7 days.

Self-do practice

Question 1 of 3 · Score 0/0

How many minutes are there in 2 hours?

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