David Chalian
CNN explains how the network projects who will win the presidency
01:54 - Source: CNN

Editor’s Note: Katia Hetter is CNN’s Senior Editor for Science and Wellness. Her views about math (and her love of it) are her own.

CNN  — 

I saw you, John King, doing complicated math on CNN’s famous interactive map. I saw you, Bill Weir, renowned CNN climate correspondent, doing hard math on a piece of paper.

I grabbed my smartphone to add, subtract, divide and multiply along with you all week.

King, Weir, the CNN analysts who supported them and many others added incoming votes onto already counted votes, coming up with votes in the millions and percentages of votes.

Truth be told, what CNN correspondents and statistical analysts did was hard math.

“All they do is, every single time vote comes in from one of these states, they plug it into their models and their formulas, trying to ascertain a very high level of confidence,” in the results so that whoever is the number two person in these contests doesn’t have a real possibility to overtake the number one person, CNN’s political director David Chalian explained of the analysts’ role in projecting who will win an election.

But the equations we’re doing at home didn’t need to be that complicated.

As of Saturday morning, these math problems vexed the entire country. How would President Donald Trump or former Vice President Joseph Biden (now President-elect) get to 270, the number of electoral votes a candidate needs to have an absolute majority?

Here’s the math.

The math for each candidate

The vote count took longer – and continues on after he’s been declared the winner – because many people used mail-in ballots due to the coronavirus pandemic, and some states were prevented by law from counting them until Election Day. (Banned from counting before Election Day? A different sort of math problem.)

For former Vice President Joseph Biden, 253 was the number of electoral college votes he had Saturday morning, and X equaled the number of electoral college votes he needed to win the presidency. Subtract 253 from 270 and you get the value of X, which is 17. (He got more.)

For President Donald Trump, 213 was the number of electoral college votes he had Saturday morning, and Y equaled the number he needed to win. Subtract 213 from 270 and you get the value of Y, which is 57.

As of 8 a.m. ET, six states had remained too close to call. They were Alaska (3 electoral votes), Arizona (11), Georgia (16), Nevada (6), North Carolina (15) and Pennsylvania (20). Simple addition tells me that’s 71 votes, enough for either man to win the presidency.

Trump needed Pennsylvania’s 20 votes to get to 270. How did I know that? Because he needed 57 votes. Without those 20 votes, he couldn’t get enough votes from the remaining five states (3 + 11 + 16 + 6 + 15).

With only Pennsylvania’s votes, Biden got enough to win. That’s because 253 + 20 = 273. It’s straightforward addition.

So many people say they’re not good at math, and we all waited, somewhat patiently, for the math to be decided by other people.

“Unfortunately, math is still portrayed as mysterious in our culture,” my friend, math tutor Pam Bee-Lindgren, told me. “We treat people analyzing the vote count as if they are wizards with unknowable powers, instead of ordinary people who kept going with math.

“It’s just like going from reading a picture book to reading a novel – and getting so fascinated with words that they became writers themselves, except with numbers,” she said. “And then math becomes normal, not mysterious, useful, instead of arcane. And our kids become comfortable with it instead of afraid of it.”

Why not do the math ourselves? It’s democracy in action, and it has never been more important.

It’s for baking, bills and pandemics

Math isn’t just for voter counters or math lovers. It’s for people telling time, measuring for recipes and figuring out how to pay the rent, buy food each month and pay for transportation.

“We tell time, we estimate how much time is left before the cookies are done in the oven, we measure wood or fabric for a project, we estimate if we have enough money to fill up the gas tank, we measure out flour and sugar to bake a cake,” said Bee-Lindgren, who’s based in Decatur, Georgia.

It’s for politicians debating coronavirus vaccines, pandemic relief, unemployment benefits, the cost of health care, tax breaks and even US Secret Service protection costs.

“The math of epidemics is the math of exponents, of numbers blowing up rather than steadily increasing,” she said.

More complicated math supports newsrooms around the globe making predictions about who will win this presidency, and decide the math of our lives for the next four years. But at the heart of the vote is the math of votes being removed from their envelopes and counted to add up to the highest vote total this country has ever seen.

We know that because we added up the number of votes cast in 2020, and subtracted the 2016 number from the 2020 number.

Get your kids excited

It’s important to teach our children the connection between math and real life.

Here’s how Bee-Lindgren recommends you start.

“One equation can let them figure out the cost of a favorite jacket on sale, how much to tip a restaurant server, how much they’ll owe in sales tax on a bottle of soda,” she said. “And, in understanding the tax on that soda, they can grow up to adults with opinions informed by facts that politicians need to hear, or that they, as politicians themselves, can do something about.”

Get CNN Health's weekly newsletter

Sign up here to get The Results Are In with Dr. Sanjay Gupta every Tuesday from the CNN Health team.

“So much of human experience is tied to steady increases or decreases – how much a child grows each year, how much money you’ll accumulate on a weekly paycheck.”

Math. It won’t always tell you what you want to hear, but it can tell you where you are.