Is mathematics useful in everyday life?

by David Radcliffe

To be honest, I don’t know the answer to this question. Teachers are supposed to teach students how they will use mathematics in daily life, but I find myself unconvinced by many of the supposed practical applications of mathematics.

Here is a typical example of a practical math lesson, from Yummy Math. The students are asked to adjust a recipe for mashed potatoes to accommodate various numbers of guests for Thanksgiving dinner. The lesson appears to be well-designed, and I have no objections to any of it, except that the questions seem rather dull.

But is it really necessary to be able to convert a recipe by hand? If you use any of the major websites for recipes, then they will convert the recipes for you with a click of a button.There are also websites that will allow you to enter your own recipes and convert them to different quantities. The average person no longer needs to know how to convert a recipe.

The same is true for computing interest payments on a mortgage, or any kind of routine calculation. If it is a problem that people typically encounter in everyday life, then there’s an app for that. Of course, the people who write the apps need to know the math behind them, but for most people this is unnecessary.

So, if we don’t need math to solve routine problems, then what is left? Non-routine problems! We learn math (in part) because we hope to solve problems that are unique to our situations; because we have questions that nobody has ever thought to ask, let alone answer; because we want to find better ways to do things. Also, understanding mathematics allows us to formulate questions that could not be asked (or even thought) without mathematics.

The paradox is that we can’t tell students how they will use math, even though it is tremendously useful. As soon as we name an application of math that our students are likely to encounter, we know that other people have encountered the same problem and solved it before us, and there is little need to solve it again. The goal of a math teacher should be to prepare students to answer questions that we cannot even conceive.

Or maybe not. I’m just rambling. Thanks for reading this far.