Scientific American presents Math Dude by Quick & Dirty Tips. Scientific American and Quick & Dirty Tips are both Macmillan companies.

If you're anything like me, you don't exactly love doing long division. Which is exactly why I avoid it as much as I can. Of course, one way to avoid doing division the old fashioned way with paper and pen is by using a calculator. Most of the time, that's exactly what I do.

But the truth is that sometimes calculators—or phones with calculators—are inconvenient. And sometimes you need to do division right there on the spot in your head. How can you do it? Keep on reading to learn 5 simple things that you can do to take your mental division skills to the next level.

Tip #1: Approximate If You Can
The first thing you can do to speed up a lot of the mental division problems you'll encounter is to stop and think about just how accurate you need the answer to be. Sometimes you need an exact answer, or perhaps an answer that's accurate to two decimal places, or three decimal places, or something else specific like that. But a lot of the time you really just need a ballpark estimate.

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