I was recently watching a ted talk where a guy is multiplying multi digits on the fly and basically just flexing on calculator peasants like me. I'm going to try and learn the skill set for my job to double check my work and also any future tests I take like the GMAT. Wondering if anyone on WSO has attempted the same and has any tips on where to start (Online lectures, Books, etc.....)
Jun 08, 2020
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“... I believe it was the single biggest reason why I ended up with an offer...”
Is this what non-targets are doing now?
Don’t get jealous of me when I answer the MD’s question on the fly. Bum fuck nowhere state is going to be looking pretty good.
Mental math can be improved upon if you dedicate time towards it. I've seen some friends do this to prepare for a coding competition but i don't know how much time and energy it would take.
google Trachtenberg system, learned about it in my proofs and logics class... it's a little difficult to grasp but with practice it can be used efficiently
Thanks, I’ll look into this
Why would anyone waste their time on this? There are far more productive things to learn.
One time in college I memorized a bunch of random double digit multiplication problem sets (32 x 37, 73 x 89, etc.)... fast forward a few months at a super day for banking at a BB, and one of the hardo MDs asked me one of these double digit math questions .... well it was one of the problems I memorized and you should have seen his face when I answered it within three seconds.... ahhhh good times, failed the rest of the super day horribly though.
You don't have to memorize to get these in ~5 seconds. Here is my strategy that I would use for both of these
32(40) = 128(10) =1280
32*3 = 96
1280 - 100 + 4 = 1184
73(90) = (70+3)9(10) = (630+27)10 = 6570
6570-70 = 6500 - 3 = 6497
I mean, he did a fricken TED Talk, so he's probably pretty successful...
Was it a TED talk or a TEDX? there’s a difference...
While I agree with everyone that it is really pointless, it can be learned. A quick way to get started is to look at a digital clock and do permutations of every basic (add, subtract, multiply, divide) calculation possible with the digits. I do this to fall asleep and have since I was a kid.
Don't think it's worth the time given that you're a 1st year RE Commercial Analyst...
This is almost pointless to learn. However, if you can use it occasionally and people will be impressed. I learned it years ago for a quant job interview, didn't get the job...
x
Time would be better spent doing percentage calculations rather than long multiplication or division tables. Especially if you’re in RE
If you are born with the talent or you already received training as a kid, it's a big plus, but I wouldn't suggest you spending time learning it now.
Being able to figure out within 3 seconds how much the price would change if cap rate goes from 5% to 4% is much more important.
Go learn to play some (any) teamsport, start there. Don't waste time on this shit
wolfram alpha, siri --> ftw
Little do people know, some prop shops test you on this...
I interviewed for quant trading positions at Optiver and IMC (Big Chicago options trading prop shops) and mental math and IQ tests were the entirety of their first round.
There are lots of techniques related to this that are actually easy to pick up.
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