Innumeracy pisses me off.
People never say “I can’t read!” But many will say “I can’t do math!”
Ridiculous. Of course you can do math. And if you practice, you can get better at it.
I used to be one of those people who avoided math. I struggled with math as a kid, and I was led to believe that math was hard for me because I was a girl. Other parents who watched their daughter sob over arithmetic at the kitchen table might have helped, might have hired a tutor, might have called the teacher to see what was going on. My parents didn’t care. They didn’t think anyone needed math beyond the ability to calculate a restaurant tip or estimate a grocery bill. And so I suffered at the kitchen table, math book open, for years.
My school system grouped students according to their general “smartness” – the smartest kids in the “red” group, middle kids in a “white” group and the dumbest kids in the “blue” group. (Can you tell I grew up the 70s?) These groups never mixed. I was in “red” because I was really great at reading, writing, social studies, science and everything else but math. I got pushed along with the rest of the “reds” through elementary school and was grouped into a similar system in middle school.
Things fell apart in high school. My struggles overwhelmed me and I got a C’s and even one D in Algebra II sophomore year. I had thought about studying medicine as a kid, but I knew you needed great math to be a doctor, so I shelved that ambition and focused instead on what I was good at – writing and reading.
Instead of continuing with the “red” crowd into Trigonometry and Calculus, junior year I downshifted into a remedial math class. I wanted to study what was on the SATs (a college entrance exam) so I could get a decent score and get into a decent college. The remedial class basically drilled you on the SATs – you know, “volume of a cone,” simple algebra, and crap like that. In higher math, I was destined for more C’s and D’s, but in this class I stood a chance. My guidance counselor told me this class would mar my transcripts for college, but I didn’t care. I was cutting my losses. Besides, I thought, I really want to learn this stuff.
To my amazement, I did well. The teacher was great and something just clicked in my head. Math was a lot easier for me after that. I actually got 10 points more on the math than the verbal part of the SAT. I really enjoyed physics. Who would have thought?
I use math all the time on the job. As a journalist, I cut a niche beat for myself in data-heavy analytics. When I joined the business world, I learned how to read companies’ earnings reports. I deal with statistics every day.
I also practice all the time. If you want to get better at math, you need to flex your muscles. Here are some ideas to help you:
- Calculate tips in your head. This is very easy! You do not need a calculator! Let’s say your bill comes to $82.50 before tax, and you want to leave a 15% tip:
- 10% of $82.50 is $8.25 (just move over the decimal one place).
- 15% is just 10% plus 5%. So cut the $8.25 in half ($4.13) and add it to the $8.25 = $12.38. I usually round up to the next dollar, so leave that waitress $13!
- If you want to leave 20%, just double the 10% = $16.50!
- Estimate your grocery bill. (This would make my parents proud, anyway.) Just an estimate is OK:
- Weigh your produce and other items weighed at checkout (there’s usually a basic scale nearby) and estimate the cost. If those tomatoes are $2.99 a pound and you’re buying 2.5 pounds, that’s $7.50 for tomatoes!
- As you shop, keep a running tally in your head of everything you buy. Bread, eggs, milk, etc.
- Subtract any coupons or special sale prices offered at the register.
- See how close your estimate gets to the actual tally.
- BONUS ROUND: If your estimate is off, it might not be you. Maybe an item rang up incorrectly. I have saved myself many dollars over the year by knowing about what I should pay and spotting errors on the receipt.
- Calculate sales taxes. Taxes vary depending on where you live. If you don’t know what your standard sales tax is, find out. Whenever you go shopping, calculate that sales tax in your head based on what you’re buying. For example:
- A $50 shirt, $20 belt and $80 pair of jeans = $150.00 worth of stuff.
- Let’s say your sales tax for clothing is 7%. You can calculate this the same basic way you did for tips, or make it easier by adding the tax up in 1% increments.
- 1% of $150.00 – $1.50 (move over the decimal two places). $1.50 times 7 = $10.50. That’s 7%!
- If you like to work with even numbers, maybe think of it this way: $1.50 + $1.50 = $3 – that’s 2%. Do this twice more, for $9 (that’s 6%) And add that last 1% for $10.50.
- Add the stuff and the tax. Total you owe for fashion = $160.50.
- Calculate the true cost of sales items. Lots of times a sale will offer, say, 30% off the full price of an item, and then you might have a coupon for an extra 10% off. You can’t just add those two discounts together to get 40% off. Many people try to do this. They are wrong. The store is going to take the 30% off the full price first, then take 10% off of the discounted price. Sneaky, eh?
- Let’s take our $150 clothes example from above. If the items were 40% off, the discount would be $60 and the items would cost $90.
- The real way discounts happen, it looks like this: 30% off of $150 is a discount of $45, so the items would cost $105. Then an additional discount of 10% would equal only $10.50. So you’d pay a total discounted price of $94.50. Still a deal, but a bit more than you might have thought if you hadn’t done the math!
- BONUS ROUND: Calculate the tax!
I could go on and on. Try it! Exercise those math muscles! The world runs on math. A basic competency will get you far in life – beyond just knowing how much to leave the waiter, you’ll understand the true cost of mortgaging your house, or paying off a car loan, or figuring out a savings plan.