When Am I Ever Going To Use This Again?

“I don’t understand why I have to learn this. When am I ever going to use this again?” is a query

students frequently ask their math teachers. It s often delivered as a whine.

I’ve had this question rolling around in my head during this winter break. I’m been trying to mentally note when I used math in my everyday activities. Frankly, I’ve lost track because I literally use math every day, usually every waking hour of every day.

Two examples:

Out to lunch

My wife and I went to lunch with two other couples.

We added 20% to the total bill, then divided by 3 to figure out how much each couple owed. Pretty straightforward, right? 

Yeah, That’s algebra.

The variable X represents how much each couple needs to pay. Y represents the total amount of the check. Here’s how that looks in algebra-speak:

You might not think about it in terms of X’s and Y’s but they’re just placeholders for real numbers in this example.

Family vacation

My family is planning an international trip. We’re looking at the cost of flights, meals, hotels, ground transportation, tours and more. Our trip may include stops in two different countries. We are dealing with exchange rates from dollars to two different currencies.

Here’s how that process looks when written as sixth grade common core state standards:

• Fluently add, subtract, multiply, and divide multi-digit decimals using the standard algorithm for each operation.
• Understand the concept of a ratio and use ratio language to describe a ratio relationship between two quantities.
• Use ratio and rate reasoning to solve real-world and mathematical problem.
• Find a percent of a quantity as a rate per 100; solve problems involving finding the whole, given a part and the percent.
• Write, interpret, and explain statements of order for rational numbers in real-world contexts.

And this is why you see so many word problems in your math classes. Life is just a series of word problems. When you buy lunch at Chipotle they don’t hand you a worksheet so

you can figure out how much change you have coming back, they just hand you your change. Is it correct? Did they give you back what you were owed? How do you know?

Like it or not, you will use math in the “real world” all the time. It doesn’t matter what you want to do for work. Whether you’re an engineer, nurse, poet, artist or plumber you will use math. LIfe will be easier for you the better your understanding of how to use math to figure things out.

And that’s the way it is.