Decimals Explained

Let’s begin by looking at what decimals look like. Decimals are numbers that have decimals points at some position in these numbers.

And that is making sense. Decimal points are \(dots,\, periods,\, spots, \,or \,smudges\).

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1. Which of the following decimals is equal to \(\frac{1}{100}\)?

A.\(0.1\)

B.\(1.1\)

C.\(0.01\)

D.\(1.01\)

Question 1 of 3

2. Which of the following decimals is equal to \(\frac{3}{10}\)?

A.\(0.3\)

B.\(0.03\)

C.\(1.03\)

D.\(0.003\)

Question 2 of 3

3. Which of the following decimals is equal to \(\frac{1}{2}\)?

A.\(0.1\)

B.\(0.2\)

C.\(1.2\)

D.\(0.5\)

Question 3 of 3

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Video Transcription

Adding and Subtracting Decimals When adding and subtracting decimals, first, line up the decimals.  We have 4.23 plus 9.075.

It is the same with subtraction. 5.629 minus 0.45.

Then, if you have any empty spaces, you can fill them in with zeroes. Adding zeroes to the back of your number, to the back of a decimal does not change the value of your number. So, these numbers are still what they were. They’re still equal.

And then, we just add or subtract like we usually would. 0 plus 5 is 5. 3 plus 7 is 10, so write your 0, carry your 1. 1 plus 2 is 3, plus 0 is 3. Bring that decimal down. 4 plus 9 is 13. So, our answer, or our sum is 13.305.

Now, for subtraction. We’re going to do the same thing, except now, we’re subtracting. 9 minus 0 is 9. 2 minus 5, we can’t take 5 from 2, so we need to borrow from our 6, just like we usually would, and add a 1 on to our 2, which makes 12, 12 minus 5 is 7. And then,
5 minus 4 is 1. We bring our decimal down. And 5 minus 0 is 5. So, our result, or our difference is 5.179.

Last Updated on July 15, 2025.