Adding and subtracting decimals is actually very similar to the addition and subtraction of whole numbers, which don’t have decimals. However, seeing all those numbers to the right of the decimal point can be intimidating and makes a problem seem much harder than it actually is.
In this guide, we'll show you just how simple it is to add and subtract decimals.
Adding Decimal Numbers
Let's do a quick review of decimal place values. Each place value, or number of decimal places to the right of the decimal point, has a different name:
When you are given a decimal addition problem, check to see if the two numbers you are given have the same number of digits after the decimal point:
As you can see, 6.55 has a hundredth place value but 7.089 has a thousandths place value. Because of this, you have to add an extra zero to 6.55 in order to line up the two numbers and add them:
Now you can add the two decimal numbers:
Subtracting Decimal Numbers
Let's subtract the following decimal numbers:
These numbers do not have the same number of digits to the right of the decimal point. 5.2 has a tenth place decimal, so we have to add two zeros in order to line the two decimal numbers up:
Now that the zeros have been added, let's proceed with the subtraction of decimals:
Adding and Subtracting Decimals — It's Easy!
Now that you've worked through adding and subtracting decimals, you can see just how easy it is. All you have to do is compare the two numbers you are given, add zeros so that they have the same amount of numbers after the decimal point, and proceed with subtraction or addition.
Learning how to add and subtract decimals will make it easier to move on to more complex concepts like dividing and multiplying decimals.