Page 16 - 新思维数学学生用书4 样章
P. 16
1.2 More on negative numbers
1.2 More on negative numbers
We are going to ...
• read and write numbers less than zero, for example −6 is negative six
• understand how negative numbers are used in the real world, for
example to describe a very cold temperature or a position below
sea level.
In this section, you will use negative numbers in temperature
contexts such as temperature or being above or zero
below sea level.
An iceberg is ice that has broken off a glacier and is
now floating. There is much more ice below sea level metres
than there is above sea level. 10
0
sea level −10
−20
−30
−40
−50
−60
Worked example 3 −70
−80
The temperature in England is 11 °C. −90
The temperature in Iceland is 15 °C colder.
What is the temperature in Iceland?
Draw a number line to
help.
−15 Start at 11.
The temperature is
−10 −4 0 10 11 colder, so you jump
back 15 places.
Answer: The temperature in Iceland is −4 °C.
15
