Khan Academy: Arithmetic and Pre Algebra: Solving Percent Problems

This video demonstrates how to find the base number when given a percentage and amount. Practice problems are included. [5:26]

This video shows how to find what percentage one number is of another. Practice problems are available. [4:37]

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

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

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

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

This video solves a problem asking to determine whether presented numbers are prime, composite, or neither. Practice problems are available. [4:40]

This video explains how to find the least common multiple of algebraic expressions. Practice problems are available. [4:40]

This video shows how to calculate the total amount after a number has grown by a certain percentage. Practice problems are available. [9:43]

This video shows how to add positive and negative money amounts in the context of a word problem using a number line. Practice problems are available. [3:15]