Adding and Subtracting Decimals – Explanation & Examples

Addition and subtraction of decimals seem to be a bit complex as compared to performing the operations on whole numbers. In this article, we are going to learn how to perform the addition and subtraction of decimals with ease.

And for this case, after reading this article, you won’t spend sleepless nights worrying about how to add and subtract decimals, because the explanations have been step by step simplified for you to understand.

How to Add Decimals?

Addition of decimal numbers is done using the following steps:

• First, the decimals numbers are written one number under each other so that decimal points are lined up.
• The numbers are converted to like decimals by attaching the zeros. The number of zeros attached depends on the number with the maximum digits after the decimal point.
• The digits of each numbers are lined up so that each column contains digits in the same place.
• Addition is carried out the normal way by starting from the right to the left.
• The decimal point is then placed in the place as the numbers above it.

Example 1

Add the following decimals: 0.9, 236.8, 1.83 and 21.105.

Solution

We can solve this problem easily by following the steps outlined above:

• Convert the numbers to like decimals and arrange them one above each other.
• Perform the normal addition starting from the right.

The sum is 260. 635

Example 2

Add the following numbers: 7.39, 65.007, 213.8 and 91.2.

Solution

• Convert the numbers to like decimals and arrange them one above each other.
• Perform the normal addition starting from the right.

The answer is 377. 397.

How to Subtract Decimals?

To perform subtraction operation on decimals numbers, the following steps are followed:

• Write down the decimal numbers, in a column so that the decimal points are lined up.
• Convert the given decimals to like decimals by attaching zeros.
• Write the larger number above the smaller number in a column.
• Arrange the numbers to be subtracted a column so that the all the digits are in the same place.
• Perform the usual subtraction starting from the right.
• Place the decimal point in the answer in the same position as the numbers above it.

Example 3

Subtract: 27.59 from 31.4.

Solution

• Convert the two decimal numbers into like decimals by attaching a number of zeros.
• Arrange the numbers in a column with the smaller number being at the bottom

The answer is 3.81.

Example 4

Subtract: 402.1 – 243.86.

Solution

• Convert the numbers to like decimal numbers.
• Arrange the numbers in a column.

The answer for subtraction is 158.24.