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# Pre-algebra

If you've mastered the basics of arithmetic and are ready to learn more about numbers and operations, you're in the right place!
Community Questions
Measurement
From length to area to volume to time, thinking about how we measure things.
All content in “Measurement”

### Area basics

Area is how we thinking about how much space something takes in two dimensions such as comparing how much land one property takes up versus another. In this tutorial, we'll take a conceptual look at how area is actually measured (especially for rectangles).

### Perimeter

Have you ever wondered how much fencing you need to surround a plot of land? No? Well, you should still go through this tutorial just in case. You'll learn all about how to think about and calculate perimeter--essentially the length of the boundary of a figure.

### Rectangle area and perimeter word problems

In this tutorial, you'll stretch your understanding of area and perimeter by applying it to word problems.

### Volume of a box or rectangular prism

Volume measures how much 3-dimensional "space" an object takes up. We'll see in this tutorial that it is an extension of length (1-D) or area (2-D) to three dimensions!