## How to Measure Time Without a Stopwatch

How can you measure time without using a stopwatch? You could use the movement of the Sun across the sky, watch a pendulum swing, or burn some very special string. Keep on reading to find out how it works!...

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Jason Marshall, PhD, is a research scientist, author of *The Math Dude's Quick and Dirty Guide to Algebra, *and host of the Math Dude podcast on Quick and Dirty Tips.

Math

How can you measure time without using a stopwatch? You could use the movement of the Sun across the sky, watch a pendulum swing, or burn some very special string. Keep on reading to find out how it works!...

December 30, 2017 — Math Dude Jason Marshall

Math

What causes the Moon to change phases throughout the month? Why is it sometimes visible only during the day and other times only at night? What’s the relationship between these times and the Moon’s phases?...

September 26, 2017 — Math Dude Jason Marshall

Math

What’s the point of learning math? Why is it so important that kids are exposed to mathematical thinking? And what do parents and teachers need to know about learning real math?...

September 2, 2017 — Math Dude Jason Marshall

Math

How do they work? And how can you turn them into improper fractions? Keep on reading to find out!

July 8, 2017 — Math Dude Jason Marshall

Math

How do you quickly calculate 25 percent of a number? Or 33 percent of a number? And how can you quickly calculate percentage increases?

June 28, 2017 — Math Dude Jason Marshall

Math

What does it really mean for a satellite to orbit the Earth? What’s the math behind it? And what’s the math behind the rockets that get those satellites into orbit? Keep on reading to find out!...

June 7, 2017 — Math Dude Jason Marshall

Math

How large was the crowd at the recent U.S. presidential inauguration? Or the inauguration eight years ago? Keep on reading to find out how crowd sizes are estimated

April 12, 2017 — Math Dude Jason Marshall

Math

Are we alone in the universe? If so, why? If not, where is everybody? Thankfully, math can help us with these astronomically profound questions

March 11, 2017 — Math Dude Jason Marshall

Math

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...

January 11, 2017 — Math Dude Jason Marshall

Math

Do you know what it is that a light-year actually measures? Do you know why so many people find it confusing? And why they really shouldn’t?

December 3, 2016 — Math Dude Jason Marshall

Math

Learn how to use statistics to understand the significance of the latest political polling results and to keep yourself from being duped by misleading information

October 26, 2016 — Math Dude Jason Marshall

Math

What are half-lives? And what do they have to do with measuring the age of the solar system and predicting the effects of a morning cup of coffee? Keep on reading to find out!

August 17, 2016 — Math Dude Jason Marshall

Math

Have you ever wondered how people figured out their latitude back in the days before the Internet? Did you know you can use the same math trick they used to pinpoint your latitude today?...

May 25, 2016 — Math Dude Jason Marshall

Math

What do you get when you put a real and an imaginary number together? A complex number. No, not a complicated number (although it is kind of complicated). We’re talking about an entirely new set of numbers dubbed “complex”...

March 16, 2016 — Math Dude Jason Marshall

Math

Do you know what a limit is in math? Do you know how to define a circle using this idea? And do you know why you might want to? Keep on reading to find out!

February 17, 2016 — Math Dude Jason Marshall

The Sciences

Do you know that math can help you survive? I’m not talking about jobs, money, and feeding yourself—I mean the lost in the wilderness, life depends on it kind of surviving. ..

October 14, 2015 — Math Dude Jason Marshall

The Sciences

How can you measure time without using a stopwatch? You could use the movement of the sun across the sky, watch a pendulum swing or burn some very special string. Keep on reading to find out how it works!...

September 16, 2015 — Math Dude Jason Marshall

The Sciences

What are the odds of successfully flying through an asteroid field like the one in The Empire Strikes Back ? Are they really 3,720 to one as suggested by C-3PO? Or are they much worse…or perhaps better?...

August 5, 2015 — Math Dude Jason Marshall

The Sciences

Ever heard of the Monty Hall problem? If so, did the world famous brain teaser leave you flummoxed? If not, how does getting flummoxed—and then just as quickly un-flummoxed—sound?...

June 24, 2015 — Math Dude Jason Marshall

Arts & Culture

What's the most important holiday in May? Obviously it's Mother's Day. But did you know there's an equation that can help you celebrate Mom? Keep on reading to find out what it is!

May 6, 2015 — Math Dude Jason Marshall

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