### Theory:

1. Rohit said to his father, "The cost of petrol is $$₹ 80.50$$ today. It is $$₹ 2.30$$ more than yesterday's cost".

2. I want to reduce my weight, which is $$55.4$$ $$kg$$.

3. The price of $$5$$ litre oil is $$₹ 525.50$$.

Many sentences like these, we use in our daily life.

Do you know what numbers are $$80.50$$ and $$2.30$$?

These numbers are called decimal numbers.
A decimal number consists of two parts; a whole number part and a decimal part.
These parts are separated by a little dot or point (.) known as a decimal point.
The left side of the decimal point is known as the whole number part.

The right side of the decimal point is known as the decimal part.
1. $$580.94$$

$$580$$ is a whole number part, and $$.94$$ is a decimal part.

2. $$64.508$$

$$64$$ is a whole number part, and $$.508$$ is a decimal part.

3. $$2.07$$

$$2$$ is a whole number part, and $$.07$$ is a decimal part.