Page 5 - ตัวอย่าง Math Solution 1

1.2 Zero

Consider the following statement.
“Cherry has 500 baht. She buys personal care products for 300 baht and sweets for her

three sisters 200 baht. How much money has she left?”
Can you tell the amount of money she has left in counting number?

Cherry has no money left.
The number 0 can be represented a value between 1 and -1. It is called zero.

Hence, Cherry has no money left. She has 0 baht left.
Give examples the number 0 represents zero things.

Note

The number 0 is not nothing. For example,
Doi Inthanon has 0 Celsius. It does not mean that
Doi Inthanon has no temperature.
But it means that Doi Inthanon has very cold
weather.

The point represents 0 on the number line is on the left of 1, and the distance is away
from 1 is 1 unit.

0 1 2 3

1.3 Negative Integers

The weather forecast for some European countries in January is shown below.

France Switzerland Denmark

-18 degrees Fahrenheit -20 degrees Fahrenheit -25 degrees Fahrenheit

You can see that -18, -20, and -25 have a negative sign in front of them. A negative sign (-) shows a value

less than zero on a scale. Consider the number line below:

Unit 1 INTEGERS 9