How to study math-heavy slides when you're not a math person

If you're looking for how to study math-heavy slides, here's the short answer: don't read the formulas as math, read them as sentences. Every formula says something you can put into plain words, every symbol is a character with a name, and the fastest way to understand one is to test it with numbers small enough to do in your head. Memorizing comes after that, not before.

This isn't just an engineering problem. Business, economics, accounting and marketing majors get formula-packed lecture slides too: present value in Finance, standard deviation in Business Statistics, elasticity in Microeconomics, break-even in Cost Accounting. And they often land on people who picked those majors precisely because they weren't into math. The slide shows the finished formula, your instructor explained it in two minutes, and in the PDF it's a line of Greek letters that might as well be another language.

I study computer engineering, so I've lived with slides like these since freshman year. What follows is the method that works for me, with examples from business and economics courses, since those are the ones most students take.

First, turn the formula into a sentence

A formula is a sentence written in shorthand. Before you do any math, translate it.

Take present value, which shows up in pretty much every Finance course: PV = FV / (1 + r)ⁿ. In words: what a future payment is worth today is that payment divided by (1 + the rate), once for every period you have to wait. And with meaning: a dollar you'll get in a few years is worth less than a dollar today, and it's worth even less the higher the rate and the further away it is.

If you can say that last sentence, you understand the formula, even if you haven't memorized it yet. If you can't say it in words, you don't get it yet, no matter how well you can plug in numbers.

Under every formula in the deck, write two lines:

1. What it calculates. "Today's value of a future payment." "How spread out the data is around the mean."
2. What it says. How the parts relate: what makes the result go up, what makes it go down.

Build a legend for the symbols

Half the confusion with formulas isn't the arithmetic: it's not knowing what each letter stands for. On the slide, your instructor wrote r, n, σ or x̄ as if it were obvious, because they said it once in lecture.

Make a legend, like the one on a map, next to each formula:

• What each symbol means, in words. r is the interest rate per period; n is the number of periods.
• What unit it's in. If r is annual and your periods are months, the answer comes out wrong even though the formula is right. A lot of exam mistakes are unit mistakes.
• What's given and what you're solving for. In problems, the same formula sometimes finds the present value and sometimes finds the rate.

If a symbol isn't explained on any slide, look it up in the textbook or ask in the next class. It's a far more common question than you'd think, and the next slide almost always uses it.

Test it with toy numbers

This is the step that changes the most. Pick numbers small enough to do in your head and watch what happens.

With present value: if you'll get $110 in a year and the rate is 10%, PV = 110 / 1.1 = 100. It's worth $100 today. Now break it on purpose:

• What if the rate is zero? Then PV = FV: if money earns nothing, getting paid today or in a year is the same. Makes sense.
• What if n gets bigger? The denominator grows, the present value drops. The further away the payment, the less it's worth today. Also makes sense.

Same with standard deviation in Statistics, which looks scary because of the square root and the sigma. Take three data points, 2, 4 and 6: the mean is 4, the distances from the mean are −2, 0 and 2, squared they're 4, 0 and 4, they add up to 8, divided by n − 1 = 2 that's 4, and the square root is 2. Now you know what each piece does: measure distances, square them so they don't cancel out, average them and get back to the original unit with the root.

Edge cases (zero, one, a huge number) teach the most, because they show how the formula behaves without the arithmetic hiding the idea.

Explain every step to yourself, especially in derivations

Some decks don't just show the formula: they show where it comes from, in a chain of equations that fills the whole slide. The temptation is to skip it or copy it down as is.

What works is going line by line and asking why you get from one line to the next: what got substituted, what got simplified, which assumption got used. Say it out loud or write it in the margin. A classic experiment by Chi and colleagues found that explaining to yourself what you're reading improves understanding, and the steps of a derivation are the perfect place to do it.

One question worth asking before you sink time into it: does the exam ask for the derivation, or just for using the formula? Instructors often say so, and if not, past exams show it. If you only need to use it, understanding the idea behind the derivation is enough.

Practice with problems, not with the slide

Understanding a formula isn't the same as knowing how to use it. The slide shows you a worked example; the exam gives you a different word problem, with the numbers scattered through a paragraph.

So once you understand it:

1. Solve one problem while looking at the example from class, to lock in the procedure.
2. Solve another without looking, with different numbers. If you get stuck, look only at the step you're missing.
3. Mix problems from different topics as the exam gets closer, to practice the hardest part: figuring out which formula applies.

For the ones you'll need to know by heart, build your own formula sheet with the legend next to each one and review it covered: write each formula from memory, then check. Testing yourself is one of the techniques that pays off most, far more than staring at the sheet ten times.

Everything in how to study from lecture slides applies here too: formulas are an extreme case of a slide that needs the explanation that isn't written down, just like slides with almost no words. And if you want that explanation to end up in your notes, how to take notes from slides covers doing it without just copying.

When you need someone to explain it

Sometimes the problem isn't the method: it's that there's nobody to ask at 11 p.m. There are a few options. The textbook usually explains the formula more patiently than the slide, YouTube channels on economics and statistics cover almost every core formula, and a classmate who gets it can walk you through it in five minutes.

You can also use Filmina, a web app that explains your lecture slides out loud, one at a time, pointing at the part it's talking about. With a formula it doesn't read it symbol by symbol: it says what it calculates and what each term stands for, using the notation on your slide. If something doesn't click, you ask Mina, the chat that answers from your own material ("why divide by n − 1 instead of n?"). It has limits: it needs an internet connection, with a scanned deck it can misread a small formula, and the problems are still yours to solve.

Frequently asked questions

How do you understand a math formula?

Put it into a sentence in plain words, build a legend with what each symbol means and its unit, and test it with numbers small enough to do in your head. If you can say what makes it go up and what makes it go down, you understand it.

Do I need to memorize formulas for the exam?

It depends on the course: many allow a formula sheet and some don't. Either way, understand them before memorizing them, because a formula you understand sticks better and works on problems that don't look like the one from class.

How do I study statistics if I'm bad at math?

Start with what each formula measures and what it's for, test each one with three or four made-up data points, and practice with past exams. Most of the math in an intro statistics course is sums, averages and square roots: the hard part is knowing which one to use.

What if I don't understand a derivation on the slides?

Go line by line and write in the margin why each step follows from the one before. If you get stuck on a step, look it up in the textbook or ask in class, and find out whether the exam asks for the derivation or only for using the result.