Khan Academy: Arithmetic and Pre Algebra: Negative Numbers Introduction

Sal tackles pre-algebra in this series of videos, starting with the concept of negative numbers. Using a number line, he takes the viewer through different practical examples of negative numbers, such as temperature and bank accounts....

Guiding viewers through adding and subtracting numbers, this video includes many tips to help new learners internalize the concept of a number line. It clarifies the relationship between positive and negative numbers, including the...

This video shows how to plot fractions, negative numbers, decimals, and fractions on a number line. Practice problems are available. [1:58]

This video teaches addition and subtraction of negative numbers using a number line. Practice problems are available. [9:16]

This video shows ordering of negative numbers by relating them to their positions on a number line. Practice problems are available. [2:47]

This video shows addition of negative numbers on a number line, using absolute values. Practice problems are included. [5:41]

This video introduces and explains the concept of ratios through a number of examples. Practice problems are available. [14:13]

A video explaining the meaning of exponents and exponential notation. Practice problems are available. [9:46]

This video demonstrates how to find the base number when given a percentage and amount. Practice problems are available. [6:17]

This video shows how to find a unit rate in the context of a word problem. Practice problems are available. [2:31]