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# 5 More Tips for Understanding Weights and Measures

How much is a gram? An ounce? Or a ton? If you don't have an intuitive feel for exactly how much mass these quantities represent, keep on reading!

By
Jason Marshall, PhD
Episode #210

## Tip 3: Pounds and Soccer Balls

The weight of a standard sized soccer ball or football is approximately 1 pound.

For one reason or another, most of us have learned at some point that 16 ounces is equal to what's called 1 pound—the favorite unit (in the U.S., at least) for measuring the mass of dogs, cats, fruit, humans, and pretty much everything else.

The quick and dirty method for intuiting 1 pound of weight (or mass) is to know that the weight of a standard sized soccer ball or football (either kind) is approximately equal to 1 pound.

A few fun facts about the pound:

• The pound is abbreviated "lb," a seemingly odd choice until you find out that the pound evolved from the ancient Roman unit of weight called the libra—hence the abbreviation.
• Way, way back in the day, the monetary unit known as the British pound was actually related to the unit of weight of the same name. Once upon a time, a British pound was equal to the value of a pound of silver. Needless to say, this relationship no longer holds.

## Tip 4: Stones and Bags of Sugar

Folks in the U.S. tend to measure their weight (or mass) in pounds, but people in Britain tend to use a unit called the stone. A stone is simply equal to 14 pounds, so a person who weighs 170 pounds equivalently weighs a little over 12 stone.

My favorite quick and dirty way to think intuitively about weights in the 10-20 pound range—and thus, in the 1 stone range—is in terms of bags of sugar. Yes, you read that right: bags of sugar. Most standard-sized bags of sugar sold in the U.S. weigh 5 pounds, which means that my beloved 1 stone cat weighs a little less than 3 bags of sugar.

A Boeing 747 weighs about 370 tons.

## Tip 5: Tons, Dairy Cows, and 747s

Let's wrap things up by stepping way up the mass scale to talk about the unit known as the ton. This is one of those units which has a technical meaning, but has also made its way into colloquial usage. When something is extremely heavy, we often say it "weighs a ton."

But if we're being more precise about things, how much does that ton actually weigh? That depends on what kind of ton we're talking about.

The regular, old-fashioned ton is equal to 2,000 pounds. The metric ton, on the other hand, is equal to 1,000 kg—which turns out to be about 2,205 pounds. Either way, a ton is a ton of mass. If you'd like some quick and dirty ways to think about just how much mass this is, typical dairy cows (which, if you've ever been right next to one, you know are huge) weigh about a ton, while small cars weigh about two tons, a blue whale weighs about 200 tons, and a Boeing 747 weighs about 370 tons.

## Wrap Up

OK, that's all the weights and measures we have time for today.

Please be sure to check out my book, The Math Dude’s Quick and Dirty Guide to Algebra. And remember to become a fan of The Math Dude on Facebook, where you’ll find lots of great math posted throughout the week. If you’re on Twitter, please follow me there, too.

Until next time, this is Jason Marshall with The Math Dude’s Quick and Dirty Tips to Make Math Easier. Thanks for reading, math fans!

Dumbell image courtesy of Shutterstock.

## About the Author

Jason Marshall, PhD

Jason Marshall is the author of The Math Dude's Quick and Dirty Guide to Algebra. He provides clear explanations of math terms and principles, and his simple tricks for solving basic algebra problems will have even the most math-phobic person looking forward to working out whatever math problem comes their way.