Adding decimals can seem tricky at first, but it follows the same basic principles as adding whole numbers. By following a few simple rules, you can master decimal addition in no time!
When you’re ready to add decimals, keep these three essential points in mind:
Convert to the Same Form: Make sure all your decimal numbers have the same number of decimal places. You can do this by adding “placeholder” zeros to the end of any number that has fewer decimal places.
Align by Place Value: Write your numbers vertically, ensuring that digits with the same place value are in the same column. The most important part is to line up the decimal points.
Add Like Whole Numbers: Once everything is lined up, add the numbers just as you would with whole numbers. Don’t forget to place the decimal point in your answer, directly below the decimal points in the numbers you’re adding.
To illustrate these rules, let’s work through an example together.
Problem: Add $212.62$ and $23.8$
Solution:
Step 1: Convert to the same form. $212.62$ has two decimal places, while $23.8$ only has one. To make them match, we’ll add a zero to the end of $23.8$, making it $23.80$.
Step 2: Align the numbers vertically. Line up the decimal points and digits with the same place value.
Step 3: Add like whole numbers.
Final Answer: $212.62 + 23.8 = \mathbf{236.42}$
Adding decimals is a straightforward process once you understand how to organize your numbers. By converting them to the same form, aligning the place values, and adding as you would with whole numbers, you’ll get the correct result every time. Keep practicing, and it will become second nature!
Question: Add $3.625$, $4.76$, and $35.74$.
The Solution Steps:
Uniform Formatting: First, look at the number of decimal places. $3.625$ has three decimal places. To make things easy, we add “placeholder” zeros to $4.76$ and $35.74$ so they also have three places ($4.760$ and $35.740$).
Vertical Alignment: Stack the numbers so the decimal points line up in a perfect vertical column.
Basic Addition: Add the columns from right to left, carrying over numbers just like you would with whole numbers.