What are decimal numbers ?
Decimal numbers represent the numbers between two whole numbers. A decimal number has two parts- a whole number part and a fractional part, separated by a point. The fractional part shows the difference between the two whole numbers.
Some facts about the decimal numbers
(i) The place value of a number after the decimal point decreases to one-tenth when moving towards the right.
(ii) The trailing zeros in the fractional part do not have any place value and therefore it does not matter if you write the zeros or not. For example, if we write 9.20100, the two zeros written after 1 have no value. Thus, we can just write 9.201.
(iii) The digits written after the decimal point are read as a single digit. For example, 125.621 the digits written after the decimal point is read as six two one instead of six hundred and twenty-one.
(iv) A decimal number can be represented in both positive and negative form.
Why do we use decimal numbers
A number is represented in a decimal form when we want to write it in a more precision form. For instance, while writing length, height, and temperature we use the decimal numbers to show its precision.
A decimal number can also be represented in the form of a fraction. In such case, we have to write all the digits in the number as a numerator eliminating the decimal point and in the denominator we have to write 1 first, followed by as many numbers of zeros, as numbers of digits are there after the decimal point.
For example, if we want to represent 12.03 in fractional form, we should write it 1203/100.