Adding and Subtracting Decimals

Lesson Plan - Get It!

Audio:

Just like a marching band, an equation with decimals needs everyone to line up in the proper place in order for it to work properly!

Adding and subtracting with decimals can be more challenging than adding and subtracting whole numbers. However, with a little practice; you should be able to add and subtract any decimal number!

Watch Math Antics Addition and Subtraction of Decimals, from Michele Cooper, to learn how:

Let's see if you remember how to line up decimals so you can add or subtract them! (You can watch the video again if you're not sure.)

• If we have the numbers 4.5, 6.93, and 22; how should we line them up?

Which example below is correct:

• Did you get it right?

Good job!

If not, go back and look at it again. Once you have it, keep going!

Now, subtract 6.98 from 25. Which example is correct:

• Did you know that was the correct choice?

If so, great job!

If not, go back and look at it again. Remember, we have to add decimal points to whole numbers and zeroes to fill in missing places.

• Now, are you ready for another challenge?

Last one! Let's line up some bigger numbers: 234.78, 1270.57, and 4.0038

Hint: Put the biggest whole number first, line up by place value, then put in zeroes for the empty places. You can do it!

Which example is correct:

• Did you get them all correct, even if you had to look back and try again?

Good work!

When you're ready, move on to the Got it? section to get some more practice!