Page 27 - 新思维数学学生用书4 样章

2 Time and timetables

What do you use to tell the

time?

Do you use an analogue
clock or watch, a digital

clock or watch or

something else?

The ancients measured time using shadows. You can make a simple shadow
clock in the playground. Make sure you choose a sunny day!

Do you know of any other timekeeping devices? Try to find out about some.

There are lots of different ways to read and record the time when something

happens. In Stage 3, you used only 12-hour times. In this unit, you will learn

about the 24-hour clock.
In Stage 3 you used:

• twenty-five to nine • twenty-five minutes to nine 10 11 12 1 2

• 8:35. 9 3

Stage 4 introduces you to: 8 7 5 4

• 8.35 a.m. or 08:35 • 8.35 p.m. or 20:35. 6

You will also learn more about timetables including those that use the
24-hour clock. You will use timetables to plan journeys and work out how

long a journey lasts.

26