In decimal we will discuss how to read and write decimal numbers.

The length of a pencil is 17.2 cm. This is read as seventeen point two cm.

Now, the decimal 49.50 can be converted into a fraction as:

49.50 = 4950/100

Similarly,

(i) 1.1 = 11/10

(ii) 2.13 = 213/100

(iii) 17.2 = 172/10

(iv)14.11 = 1411/100

(v) 9.781 = 9781/1000

**So, we note that the number is divided:***(a) By 10 if there is one digit after the decimal.**(b) By 100 if there is two digits after the decimal.**(c) By 1000 if there is three digits after the decimal.***(a) The number is divided by 10 if there is one digit after the decimal.**

**For example:**

(i) 1.5 = 15/10

[We observe that in 1.5, after the decimal there is one digit so we need to divide by 10]

(ii) 12.3 = 123/10

[We observe that in 12.3, after the decimal there is one digit so we need to divide by 10]

(iii) 10.1 = 101/10

[We observe that in 10.1, after the decimal there is one digit so we need to divide by 10]

(iv) 111.2 = 1112/10

[We observe that in 111.2, after the decimal there is one digit so we need to divide by 10]

(v) 145.9 = 1459/10

[We observe that in 145.9, after the decimal there is one digit so we need to divide by 10]

**(b) The number is divided by 100 if there is two digits after the decimal.**

**For example:**

(i) 2.51 = 251/100

[We observe that in 2.51, after the decimal there is two digits so we need to divide by 100]

(ii) 12.03 = 1203/100

[We observe that in 12.03, after the decimal there is two digits so we need to divide by 100]

(iii) 19.11 = 1911/100

[We observe that in 19.11, after the decimal there is two digits so we need to divide by 100]

(iv) 11.24 = 1124/100

[We observe that in 11.24, after the decimal there is two digits so we need to divide by 100]

(v) 14.93 = 1493/100

[We observe that in 14.93, after the decimal there is two digits so we need to divide by 100]

**(c) The number is divided by 1000 if there is three digits after the decimal.**

**For example:**

(i) 1.555 = 1555/1000

[We observe that in 1.555, after the decimal there is three digits so we need to divide by 1000]

(ii) 12.005 = 12005/1000

[We observe that in 12.005, after the decimal there is three digits so we need to divide by 1000]

(iii) 2.001 = 2001/1000

[We observe that in 2.001, after the decimal there is three digits so we need to divide by 1000]

(iv) 1.112 = 1112/1000

[We observe that in 1.112, after the decimal there is three digits so we need to divide by 1000]

(v) 15.913 = 15913/1000

[We observe that in 15.913, after the decimal there is three digits so we need to divide by 1000]