Whole numbers :

​

• "whole" for complete​

Fractions​

• a part of the whole

How can a number which has a value in between 0 and 1 be expressed ?​

We can use "decimals" to express the number in between any two whole numbers.​

On the number line, there are 10 equal division between 0 and 1​:

On the number line, there are 10 equal division between 0 and 1​:

On the number line, there are 10 equal division between 0 and 1​:

​Questions:

• How to read this decimals "0.7" ?

• ​0.7 is smaller than ? but larger than ?

• **Can we remove the 0 at the front?​

On the number line, there are 10 equal division between 0 and 1​:

Lesson Objectives:

• F​ind the position of decimals on the number line

• Given a graph, use a decimal and its fraction to represent it

The value of this decimal is about / around ...​

How can we find the position of the decimal " 1.5" on the number line?

​On the number line, there are 10 equal division between 1 and 2 :

​On the number line, there are 10 equal division between 1 and 2 :

​The decimal "1.5" is read as "one point five".

​

It has a value greater than 1 but smaller than 2.

​

It is half way between 1 and 2.​

Decimals are made up of

"whole number part" and "decimal part" too

Just like what we have in mixed numbers of fractions​

Expressing the decimal "3.4" in picture

Decimals and Fractions are interchangeable ! (same value but different ways of expression)

Decimals and Fractions are interchangeable ! (same value but different ways of expression)

They are all decimals with

ONE decimal place

​211.6

43.2​

9.9

3.4

​ 1.8

0.8

0.1​

​

Decimals with 2 decimal places​

How to find the position of decimals with 2 decimal places​

on a number line?

On the number line, there are 10 equal divisions between 0 and 1​:

​

Decimals with 2 decimal places​:

​There are also 10 equal divisions​ in between 0.1 and 0.2

Fill in the decimals between 0.1 and 0.2 !​

Decimals with 2 decimal places​:

​There are 10 equal divisions​ in between 3 and 4.

Fill in the decimals between 3 and 4 !​

Decimals and Fractions are interchangeable ! (same value but different ways of expression)

click the link for exploration:​

https://www.geogebra.org/m/NSA9eAVa#material/NnxTD3pe

Decimals and Fractions are interchangeable ! (same value but different ways of expression)

Question:

how many boxes should be coloured to represent " 0.16 "?​

They are all decimals with

? decimal place

​211.6

43.2​

9.9

3.4

​

​

Lesson Objectives:

• F​ind the position of decimals with 3 or 4 decimal places on the number line

• Recognise the place value of a decimal

The orange part indicates a decimal.

What is the range of value of this decimal?​

The orange part indicates a decimal.

It has a value between 0 and 0.1

It is 0.01​

Do you think there are any more decimals "living" between 0 and 0.01 ?​

Decimals "living" between 0 and 0.01 :

Decimals "living" between 0 and 0.001 :

Further dividing​ 0 and 0.001 into 10 equal divisions:

The more 0 in between 0. and the last digit 1,

​

the smaller the decimal becomes​.

​Click the link to find out how a decimal is

getting smaller in value:

​

https://www.geogebra.org/m/NSA9eAVa#material/Wn6gYc78

Lesson Objectives:

• F​ind the position of decimals with 3 or 4 decimal places on the number line

• Recognise the place value of a decimal