Decimals

This course is a part of Pre-algebra, a 10-course Topic series from Khan Academy.

Understanding decimals conceptually, using operations with decimals, rounding and estimating with decimals, and converting decimals.

This course contains 10 segments:

Intro to decimals

What are decimal numbers? How are they like fractions?

Decimals on the number line

See how decimals can be placed on the number line, just like fractions and whole numbers can.

Rounding decimals

Learn how to round decimal numbers to specific place values. For example, round 3.14159 to the nearest hundredth as 3.14.

Comparing decimals

Let's test our understanding of decimals by comparing them to one another!

Rewriting decimals as fractions

Learn how to rewrite decimals as fractions.

Adding decimals

Honestly, once you remember one very important rule, the rest of adding and subtracting decimals is a snap. That rule is to be sure and align your decimals first. In this tutorial, you'll get a chance to practice this with us and become fluent adding decimals. We'll tackle subtracting decimals in the next tutorial.

Subtracting decimal

Just like with adding decimals, the key to subtracting decimals is aligning the decimal points. Let's practice!

Adding and subtracting decimals word problems

In this tutorial, we practice solving word problems by adding and subtracting decimal numbers.

Multiplying decimals

You've already multiplied decimals in the 5th grade. We'll show you some ways to handle slightly more complicated problems. Now you'll become super good at it with a bit more practice! Common Core Standard: 6.NS.B.3

Dividing decimals

Learn long division with decimals. Solve problems like 30.24 divided by 0.42.