**계산**

The verbal phrase “do the math” means to examine the facts and figures to reach a conclusion, especially when the answer is very clear.

For example, let’s say I love animals. I spend all my savings on caring for stray cats and dogs. When my friend asks why I never go on vacation, I can simply point to my seven cats and five dogs and say, “Money for vacations? You do the math!”

Of course, before children can do even basic math they must learn to count. But counting numbers is not the only meaning of the word “count.” Consider a famous quote by the scientist Albert Einstein. He reportedly said, "Not everything that counts can be counted. Not everything that can be counted counts."

This quote is a pun, a play on words. It plays with two meanings of the word “count.” Count means to determine the total number of something. It also means to have value or importance. Things that matter, things that are important ... count.

Let’s hear count used in a dialogue. These two friends are talking about an upcoming U.S. election. Take note that a third definition of “count” -- meaning “depend” -- is used.

A: Are you voting in November?

B: Why should I? My vote doesn’t count.

A: What do you mean it doesn’t count?! After they close the polls workers count all the votes!

A: What I mean is that voters in D.C. don’t have representatives in Congress. So, even though my vote for president is officially counted, my opinion about what should happen in my own neighborhood doesn’t count. And many people in D.C. are sick of it. You can count on that.

B: Oh, that’s right. I didn’t count that fact. I live in Maryland and have 10 representatives in Congress. So, my voice does count more than yours.

A: Hm-mm.

That is a lot of counting! After counting, many children learn to solve simple addition problems. They learn that 1+1=2 and 2+2=4 and so on and so on.

However, as we get older we learn that things often don’t add up so simply. Things that should make sense sometimes don’t, as in this example:

A: Hi!

B: Hey! Welcome to another Monday at work!

A: Yeah, thanks. Hey, why is Marissa’s purse on her desk? I thought she started her vacation today.

B: Maybe it’s her second purse. Women do carry more than one purse, you know.

A: I know that. It’s just odd. She never leaves her purse.

B: Hey, what are doing? It’s rude to go through someone’s purse.

A: I know. But I have a bad feeling. Look. Here are her house keys, her wallet, even her plane ticket. It says she’s flying out today!

B: You’re right. That doesn’t add up. Something might be wrong. Why don’t you go to her apartment and I’ll call her boyfriend.

A: I hope Marissa is okay.

B: I know.

Addition and subtraction are both part of math equations. For example, 8 + 4 = 12 or 2x ? 3 = 9. In those equations, the number 4 is a factor of both 8 and 12. And the letter x is a variable that stands in for the number 6.

The words “equation,” “factor” and “variable” are all very common in both casual and formal conversations. So, you could say getting students to finish all their homework and chores can be difficult when playing video games is part of the equation. Playing video games is a factor or variable that makes the situation difficult.

Or, let’s say I volunteer to help organize the holiday party at my office. But I did not count on how complicated it would be!

There were so many factors to add to the equation. I had to get permission to rent extra tables and chairs. I had to decorate the conference room but I couldn’t start until everyone finished their meetings. And I had to decide whether to hire a D.J. or have live music.

Also, there were so many variables I didn’t know. For example, how many people would bring guests? Did my colleagues expect to eat dinner or just snacks? In the end, the party turned out great. But the process was awful. I’ll never volunteer again!

Planning a party can be complicated. And as math becomes more complex so do the expressions.

The lowest common denominator, for example, is the smallest number that can be divided evenly into a set of fractions.

In conversation, the lowest common denominator refers to the lowest level of taste. Some television shows in the United States appeal to the lowest common denominator. They take advantage of everyone’s natural interest in gossip, violence and romance. These types of program are often vulgar, tasteless and base.