- Topics At a Glance
- Expressions
- Addition
- Subtraction
- Multiplication
- Division
- Parentheses
- Variables
- Translating Slowly
- Equations and Inequalities
- The Equals Sign
- Inequalities
**Word Problems**- How to Read Word Problems
- How to Become a Word Problem Expert
- Geometry Problems
- Averages
**Percents**- The Word "Per"
- Coin Problems
- Written Inequalities
- In the Real World
- I Like Abstract Stuff; Why Should I Care?
- How to Solve a Math Problem

Go here to review percents if you're feeling a little fuzzy about them. If you're still feeling fuzzy after reviewing that section, you should see a doctor. You may have a concussion. Hopefully, it wasn't algebra-induced.

15% of what number is 6?

This is a fairly straightforward question, so the first thing we need to do is to make sure we're interpreting it correctly. We're not looking for 15% of 6. Instead, we're looking for a number that will *give* us 6 when we take 15% of it. In this example, "what number'' translates to *x*, and "15% of'' means "0.15 times." If you take an algebra test and you get it back with a red "0.15" scrawled across the top, you'll know how well you did. Answer: not so well.

Now we solve the equation

0.15*x* = 6

and get *x* = 40. We can backtrack and double-check our work to make sure that's right. Sure enough, 15% of 40 is 6. Hot diggity.