Whether you think you can or you can’t you’re right.

– Henry Ford

During one of my first banking interviews, I was asked a classic brain teaser.

“How many pot holes are in Manhattan?”

Luckily for me, I think I’m fairly good at math. Unluckily for me, I think that I am AWFUL at geography.

So, I made a bunch of assumptions and walked the interviewer through my process.

I got to a number right around 100,000 total potholes. Turns out there are right under 10,000 potholes.

The issue? I assumed the island of Manhattan was 100 miles. It’s actually 13.4 miles. No biggie, only off by a factor of seven.

Surprisingly, I got the job and now a decade later I still hold the beliefs that I’m awful at Geography (and still great at math).

However, those beliefs are self-fulfilling prophecies in a way.

We all naturally gravitate towards what we’re good at it. So we practice it more often.

Growing up my siblings were good at math so I always assumed I was.

Whenever there was a chance to try and do mental math, I jumped at it.

Today, I still do. For example, I always calculate restaurant tips even if I’m not paying.

(Here’s a way to do it instantly: Remove one 0 from the total bill to get to a 10% tip. So if you have a $150 bill, 10% would be $15. Then just double that to $30 and you get to a 20% tip.)

When it comes to Geography though, I never try and figure out where anything is.

I just shrug my shoulders, raise my hands and immediately pull out Google Maps.

I don’t take pride in my geographic knowledge, and therefore I never practice it.

I’ve even said out loud many times that I am awful at Geography.

However, if I practiced trying to memorize Geography as often as I do mental math, I’d likely be a lot better.

Sometimes, just believing our abilities can make the biggest difference.