There’s More than One Way to Skin a Math Problem (Video)

I never was fond of the step-by-step process many of my math teachers favored. But by the time I reached high school, I figured out that math is pretty darned flexible. And in college, that lesson really took hold.

You may think that math is black and white, but honestly? There are many different ways to solve simple and complex math problems. And that’s what I explain in my latest video. Check out how you can be creative with your math solutions — and still arrive at the correct answer!

More videos are coming, so please subscribe to my YouTube channel: mathforgrownups.  Also, I hope you’ll share this video on Twitter, using #flexiblemath and post it on your Facebook page. Share the Math for Grownups love!

As always, I’d love to hear what you think. Ask your questions or share your feedback in the comments section. Were you surprised by anything in the video (like how you solved the problem I propose)? Do you have your own stories to share about how you learned to find your own way to answers? Share in the comments section!


A Gift Guide for Math Geeks (and Wannabes)

gifts for math geeks


It’s gift-giving season for most of us. In honor of the winter holidays, I’ve pulled together a little list of ideas for your math geek. Or perhaps you want to encourage someone to step a little deeper into the math pool. I’ve got ideas for those folks, too. Enjoy!

  • Math Operations Coasters
    Who knew PEMDAS could keep a table ring-free?
  • Pi Bottle Opener
    With a quick flick of the wrist and a very special number, your math geek is on her way to quenching her thirst!
  • Special Number Whiskey Glasses
    Give your favorite Scotch drinker something to really pontificate about!
  • Computation Dish Towel
    Smart clean up for the mathy kitchenista.
  • Pi Cuff
    What's more elegant than the most famous irrational number?
  • Fibonacci Spiral Necklace
    There's no denying the beauty of math's most mysterious discovery.
  • Mobius Cowl
    Whether you make your own or purchase this gift, the one-sided, 3D marvel is perfect for warding against the cold.
  • Math Club T-shirt
    It's finally hip to be a geek!
  • This one-of-a-kind book features a poem dedicated to pi, by Wislawa Szymborska. Gorgeous!
  • This picture book is a funny take on the everyday appearance of math
  • For the carpenter in your life.
  • Sneak in some geometry into your kids' art kit collections.
  • My favorite recommendation for parents who want to challenge their kids. This is a deceptively fun game for the whole family!
  • Practice logic to break the code.
  • With more geometry, Perfection tests players' ability to spot like figures before the buzzer goes off. (A blast from my past!)
  • Origami is a great way application of geometry on the sly.

Main Photo Credit: peddhapati via Compfight cc. All other photos from product websites.

What’s your favorite geeky holiday gift? Share your ideas in the comments section.

Let Me Interview You for a Math at Work Monday Post!

Math at Work Monday

Since launching this website in 2011, Math at Work Monday has been an extremely popular feature. Teachers let me know that they love sharing insight from these interviews with their students. (What better way to answer the question, “When am I ever going to use this stuff?”) Other grownups have told me that the interviews help them identify when they’re using math in their everyday lives.

Over the years, I’ve interviewed a variety of different people — from an astronaut to a fish hatchery technician to a glass artist. All jobs are terrific fits — because as we all know, Everyone Does Math.

(Did you catch my Everyone Does Math video? Check it out!)

In fact, the series has been so successful, I’m launching a special printed option for teachers and homeschoolers, including unique student-directed questions. I’ll start with one set of my favorite interviews, which can be downloaded as printable worksheets for use in the classroom or at home. Stay tuned for the details, coming in two weeks!

Now I need your help! I’m looking for new people to interview in the next month. If you or someone you know is up for it, let me know. You can email me at [email protected] (include their names and email addresses). If you’ve been around for a while, you know that the process is simple. My wonderful assistant, Kelly emails a list of questions — yes, everyone gets the same questions! — you respond to the questions and email them back to Kelly. That’s all. Painless.

So what kind of folks am I looking for? You name it!

  • dentist, orthodontist, dental hygienist
  • pet groomer, dog walker
  • EMT
  • chiropractor
  • divorce attorney
  • security officer, military personnel, state trooper
  • archeologist
  • chef, pastry chef, caterer, butcher
  • makeup artist
  • interior designer
  • surgical nurse
  • prosthetic engineer
  • truck driver, tow truck owner
  • actuary

But you can probably come up with even more great ideas. If you have suggestions (but don’t have someone to recommend), go ahead and post them in the comments section.

I’m so proud of the Math at Work Monday series, and I thank you for making it so popular and for making it possible. I look forward to receiving your recommendations. Remember, email me with potential interviewee’s names and email addresses at [email protected].

Photo Credit: stefanweihs via Compfight cc

Everyone Does Math, Every Day (Video)

Think you don’t need math? Think again! Math is everywhere, and much of the time you might not even realize that you’re doing it.

If you remember wondering when you’d ever use math as a grownup, click on my next Math Manifesto video above.

And don’t miss out on other videos, including: Everyone Has a Math Gene.

More videos are coming, so please subscribe to my YouTube channel: mathforgrownups.  Also, I hope you’ll share this video on Twitter, using #idomath and post it on your Facebook page. Share the Math for Grownups love!

As always, I’d love to hear what you think. Ask your questions or share your feedback in the comments section. After watching the video, are you convinced — as I am — that you do math every day? Why or why not?

Stop Freaking Out About Ebola (Because: Math)



When I read Richard Preston’s The Hot Zone in the mid-1990s, I was terrified. This was the first I had heard of a scary new disease called ebola. I was working for an AIDS Service Organization at the time, so I understood — better than most — how blood-borne infectious diseases are contracted. Still, the images of how the victims of this virus die are still with me. Horrifying.

But I’m not at all afraid of ebola today. Not one little bit. Why? Math.

It’s difficult for ebola to spread. Really difficult. Like HIV, the ebola virus only lives in bodily fluids, including blood, saliva, mucus, vomit, semen, breast milk, sweat, tears, feces and urine. (HIV is only transmitted through four bodily fluids: semen, vaginal fluids, breast milk and blood.) Transmission can occur when infected bodily fluids come into contact with a person’s eyes, mouth or nose, or an open wound or abrasion.

Compare this to measles, which is transmitted through the air. The measles virus lives in the mucus lining of the nose. A sneeze or cough can release virus-infected droplets into the air. Breathe in the air with little measles droplets, and unless you’ve been vaccinated, it’s very likely you’ll see a tell-tale rash in a few days.

Since measles is highly contagious for four days before symptoms appear, a person can transmit the virus without even knowing he has it himself. According to the CDC, measles is so contagious that if one person has it, it will spread to 90 percent of the people who come in contact with that person (if they are not already immune, thanks to the vaccine).

It’s All About the R0

The way a virus is transmitted helps determine how contagious the disease is. And the big deal here is something called R0 or “reproduction number” (also called “r-naught”). R0 is the number of people that one infected person will likely infect during an outbreak.

Those of us of a certain age might remember a shampoo commercial that illustrates this perfectly.

Like Fabrerge Organics shampoo, ebola’s R0 is 2. When one person contracts ebola, it is likely that two others will become infected. Yes, those numbers add up — and they have in parts of Africa.

Now take a look at measles, with an R0 of 18. When one person gets measles, it’s likely that 18 people around him do too. Then each of those 18 people spread the virus to 18 more people. In one generation of this infection, 18 x 18 (324) have contracted measles. That’s compared to only 2 x 2 (4) people who will likely contract ebola in one generation of the infection. In fact, measles is still one of the leading causes of death in children around the world. According to the WHO:

Measles is still common in many developing countries – particularly in parts of Africa and Asia. More than 20 million people are affected by measles each year. The overwhelming majority (more than 95%) of measles deaths occur in countries with low per capita incomes and weak health infrastructures.

But measles is not a major threat in the U.S., and we all know why — the measles vaccine. Ebola has no vaccine, but a relatively strong health care system in our country and its very low R0 makes ebola a low threat, compared to other viruses, like HIV and certain strains of influenza.

The scary thing about ebola is not how quickly it spreads but how basic medical care can keep it from spreading. We have that basic care here in the U.S. Large swaths of Africa do not.

And along with a low R0, the ebola virus has a relatively short infectious period — about a week. On the other hand, HIV is infectious for years and years — many of those years while the infected person has no symptoms or does not even test positive on an HIV test. The relationship between time and infection matters, too.

You Should Worry About Other Things Instead

For example, the National Institutes of Health (NIH) reports that each year, about 5,000 people under the age of 21 die in alcohol-related incidents, including car crashes, falls, burns, homicides, suicides and alcohol poisoning.

According to the Federal Reserve, Americans held $229.4 billion in consumer credit (outstanding household debt, including credit cards and loans) in July 2014.

The global sea level is rising at alarming rates, according to the National Oceanic and Atmospheric Administration (NOAA). Before 1900, these levels remained constant. Since 1900, the levels have risen 0.04 to 0.1 inches per year. But beginning in 1992, that rate climbed to 0.12 inches per year. This translates to much greater likelihood of flooding in coastal areas (including the neighborhood where I lived for 10 years).

And we should be concerned about ebola in Africa, mainly because we can do something about the higher rates of ebola infection and deaths there.

But ebola in the United States? Really, this shouldn’t be a worry for you. Let the math ease your mind.

Photo Credit: CDC Global Health via Compfight cc