Adding decimal numbers is just like adding whole numbers, but with a little extra attention to the decimal point.
The decimal point separates the whole part of a number from the parts smaller than one. When you add decimal numbers, it's important to line up the decimal points so that you are adding the numbers in the same place value.
For example, let's say you want to add 2.5 + 1.6. You would start by writing down the numbers with the decimal point lined up:
Next, you would add the numbers just like you would with whole numbers, starting from the right-most column and working your way left.
The answer is 4.1, and you can see that the decimal point stays in the same place as in the original numbers.
It's important to be careful when adding decimal numbers and to always line up the decimal points. With a little practice, you'll be adding decimal numbers like a pro!