Mental Math -- How to Start?

Look up a guy named Arthur Benjamin, he has a few books on it.

Try the Mental Math app by Magoosh. It has flipcards on generic math problems and the tricks that help you to solve them.

This right here...

Our generation has relied so heavily on calculators.

I've tried to steer myself away from calculators the last year or two in attempt to develop basic mental math skills. Once I come across a problem I'll initially work it out in my head and come up with an answer, I'll check my answer with a calculator and compare it with the one derived in my head. This is a rather unconventional approach but I can definitely see improvement since I've started practicing this method.

There's really no easy trick for mental math - it's all basically experience with developing the skill. Unless you're a natural wiz at mental math, which I'm sure some of you on here will be quick to admit. Nonetheless, keep at it until you become confident in your ability. Before you know it, you'll be excited for those mental math interview questions to come.

"Anybody have any suggestions on how to build my mental math ability from the ground up?"

You can re-enroll in the 4th grade.

I suck at this too.

I just try not to panic and think through things calmly. I always take a little extra time checking my work.

People at work definitely put too much emphasis on this ability tho IMO. We're not mathematicians

Check out those brainteaser, mental math apps on the app store. Tons of them for free too I think

I'm a high school senior, but I've done math competitively, so I do have some experience doing mental math. A bunch of people are saying you should memorize a bunch of tricks, but I disagree. Hear me out.

Tricks are great. However, they are not replacement for practice. Before you start memorizing tricks, you should just do a bunch of arithmetic drills with pencil and paper. Get comfortable with numbers. You eventually build up a sort of intuition with numbers with enough mind-numbing, repetitive practice. After developing this intuition, you can really take advantage of the "tricks" and get acquainted with mental math. But once again, I don't really think you can do mental math very well unless you master pencil-and-paper math first.

Nearly a quarter of one of my BB FT interviews was purely on doing finance/accounting related math in my head. I was nervous about the interview since it was my first FT interview during senior year of college and struggled to do basic percentages and calculations without making simple mistakes along the way. Although I had all the qualifications and had networked my arse off, I didn't get the offer. :(

I learned the hard way that although mental math has almost no importance in IB once you get the job, it can be a deciding factor in interviews.

There are plenty of apps available on iPhone and Android that have "flash card" like simulations testing your mental math ability. Download a few and practice like your life depends on it. Eventually, it will click, or it won't. Either way, you'll know where you stand.