Scientific American presents Math Dude by Quick & Dirty Tips. Scientific American and Quick & Dirty Tips are both Macmillan companies. Long time math fans may remember our first foray into the world ...

The $130 fishing rod was first marked down 40 percent, and now it’s an additional 25 percent off. How much will it end up costing? If you’re not sure how to go about figuring this out, you’re not ...

Have you ever stared at a spreadsheet, struggling to make sense of percentage calculations that just don’t seem to add up? Whether it’s a confusing formula, a misstep with zero values, or an ...

What can be said about math riddles? Everyone in the world has a love-hate relationship with them. You can hate math, but you have to accept that it is vital in our day-to-day lives. The world cannot ...

If you are using Microsoft Excel to manage numerical data, at some point you're inevitably going to display percentages. Doing so can give you a new insight, or make summarizing heaps of data a bit ...

Writing one number as a percentage of another number is a common, everyday necessity. For example, it's used for calculating percentage scores on tests or working out costs on a project. A maths test ...

Let's face it: Even the best budgets can't always predict your actual expenses. Things happen. Unexpected costs arise. That's life. That's why it's so useful to review your budget after a project is ...

How to calculate percentages is easier than you think. Quick, what’s 36% of 25? Or how about 250% of 20? Learn a quick and dirty tip to help you calculate all of those pesky percentages in your head.