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Tiresias · Mar 7, 2007, 08:23 AM

How many digits can you multiply in your head?

d4nth3m4n · Mar 7, 2007, 08:30 AM

well, let's get it over with.

how many can you multiply? let's hear about how smart you are...

seriously though, what are you, 17? first winter in the dorms?

Tiresias · Mar 7, 2007, 08:33 AM

Don't jump to conclusions.

As it happens, I voted option 2. I'm terrible at math. I'm just wondering what the average is.

Big Mac · Mar 7, 2007, 08:35 AM

I can multiple any single digit by any double digit, but it may take me a number of seconds depending on the case. Do you mean be able to do it instantly?

RAILhead · Mar 7, 2007, 08:38 AM

37!

Tiresias · Mar 7, 2007, 08:40 AM

Originally Posted by Big Mac

I can multiple any single digit by any double digit, but it may take me a number of seconds depending on the case. Do you mean be able to do it instantly?

Well, let's say there was some time constraint (like someone waiting for the answer) and it was important to get it right (like, money was at stake). Would you be confident in your ability to do the math in your head, or would you say: "I need a calculator" ?

By the way, dantheman: You voted: "Any double-digit number by any triple-digit number"

That's amazing.

Big Mac · Mar 7, 2007, 08:47 AM

Originally Posted by Tiresias

Well, let's say there was some time constraint (like someone waiting for the answer) and it was important to get it right (like, money was at stake). Would you be confident in your ability to do the math in your head, or would you say: "I need a calculator" ?

If the person could afford to wait a few seconds, I could do it mentally. Otherwise I'd need a calculator.

wataru · Mar 7, 2007, 09:18 AM

That's not math. That's arithmetic.

centerchannel68 · Mar 7, 2007, 09:29 AM

.... must...resist.... asian joke... to spite.... Tiresias.... must.... resist....

Tiresias · Mar 7, 2007, 09:33 AM

Originally Posted by wataru

That's not math. That's arithmetic.

Whatever.

andi*pandi · Mar 7, 2007, 09:44 AM

Originally Posted by Tiresias

Would you be confident in your ability to do the math in your head, or would you say: "I need a calculator" ?

Neither. I would say: "I need a pencil and paper."

Being able to do it all in your head isn't the test of knowing how to do it, it's a test of having a really good memory.

Dakar² · Mar 7, 2007, 09:49 AM

Originally Posted by centerchannel68

.... must...resist.... asian joke... to spite.... Tiresias.... must.... resist....

I'm not asian, so you can't count on me being very reliable.

dcmacdaddy · Mar 7, 2007, 09:57 AM

I selected triple-digit by triple-digit.

Now, if you wanted it to be a quick, almost immediate calculation, than my answer would be no. But, give me a minute and I could do in my head ABC x DEF with a high degree of accuracy.

Gossamer · Mar 7, 2007, 10:11 AM

Originally Posted by andi*pandi

Neither. I would say: "I need a pencil and paper."

Being able to do it all in your head isn't the test of knowing how to do it, it's a test of having a really good memory.

Doing it in your head doesn't mean you have the answer memorized, it means having a good method that works well.

Railroader · Mar 7, 2007, 12:29 PM

Originally Posted by dcmacdaddy

I selected triple-digit by triple-digit.

Now, if you wanted it to be a quick, almost immediate calculation, than my answer would be no. But, give me a minute and I could do in my head ABC x DEF with a high degree of accuracy.

Same here.

Originally Posted by RAILhead

42!

Fixed™

OreoCookie · Mar 7, 2007, 12:31 PM

Being able to add and multiply has nothing to do with being good at math. Or so I hope

sek929 · Mar 7, 2007, 04:26 PM

With a cell-phone calculator so readily at hand I've found myself getting worse at simple arithmetic over the years.

I voted 1-9, though I know 1-13 technically.

GSixZero · Mar 7, 2007, 04:53 PM

If you give me about twenty seconds per digit in the smaller of the two numbers, I can multiply any two numbers together.

Dakar² · Mar 7, 2007, 04:56 PM

I can count all the way to ∞

osiris · Mar 7, 2007, 04:57 PM

I can count all the way up to Q.

Railroader · Mar 7, 2007, 05:35 PM

I can name that tune in 3 notes.

iMOTOR · Mar 7, 2007, 07:45 PM

I can count all the way up to π.
I have no idea what that means- somebody please tell me

Parvez · Mar 7, 2007, 08:09 PM

Speaking of Math, do you guys watch the show "Are you smarter than a Fifth Grader?" on Channel 5: Fox 5

It's hilarious that most high school students do not know how many sides does a triangle have and a 5th grade knows.

Rev-O · Mar 7, 2007, 08:42 PM

Double by double is really pretty easy if you break the numbers down into constituent parts (rounding is often useful as well) and then add/subtract the results to obtain the answer. 59x21 is the same thing as (60x21)-21, or ((6x20)+6)x10)-20-1. The math is really easy, keeping track of the parts your working with is the tricky part.

Ghoser777 · Mar 7, 2007, 08:46 PM

Once you get high enough up in math, you stop adding, subtracting, multiplying, etc... heck, most of the time you don't even work with numbers!

Ganesha · Mar 7, 2007, 08:49 PM

If you can do "The multiplication table from 1-9" you can do "Any two triple-digit number", if you can remember 3 4-digit numbers for a short period of time.

imitchellg5 · Mar 7, 2007, 08:58 PM

Where is the option for "You suck at anything Math related?" That's me pretty much.

TheMosco · Mar 7, 2007, 10:29 PM

3.000 A 200501 - MA 1021 CALCULUS I
3.000 C 200501 - MA 1022 CALCULUS II
3.000 C 200502 - MA 1023 CALCULUS III
3.000 B 200502 - MA 1024 CALCULUS IV
3.000 C 200601 - MA 2621 PROBABILITY FOR APPLICATIONS
3.000 C 200602 - MA 2071 MATRICES&LINEAR ALGEBRA I
3.000 C 200701 - MA 2611 APPLIED STATISTICS I
3.000 B 200602 - MA 2201 DISCRETE MATHEMATICS

I suck at math. Even with that, my GPA is still over a 3.

tie · Mar 8, 2007, 02:33 AM

Originally Posted by wataru

That's not math. That's arithmetic.

Exactly.

Chuckit · Mar 8, 2007, 03:30 AM

Originally Posted by wataru

That's not math. That's arithmetic.

My thought exactly. If being able to add and multiply were the criteria for being "good at math," I'd be a bona fide mathematician.

Mastrap · Mar 8, 2007, 07:55 AM

I hated math at school, and still consider myself to be terrible at it, but even I don't see the big deal in multiplying three digit numbers. I'd just need a little time.

Calculus, on the other hand....

wataru · Mar 8, 2007, 08:27 AM

Originally Posted by Tiresias

Whatever.

You clearly know exactly dick about mathematics.

Tiresias · Mar 8, 2007, 08:56 AM

Originally Posted by wataru

You clearly know exactly dick about mathematics.

Wrong "whatever" dude. That "whatever" meant "tomayto-tomahto" not "you're talking crap"

But your estimation is entirely incorrect. As it happens, I know slightly less than dick about mathematics.

Dakar² · Mar 8, 2007, 09:16 AM

MacNN: Where threads about math get personal.

ghporter · Mar 8, 2007, 09:37 AM

Originally Posted by Tiresias

Don't jump to conclusions.

As it happens, I voted option 2. I'm terrible at math. I'm just wondering what the average is.

The answer is 42, but you need to come up with the question.

Seriously, multiplication can be quite simple if you break down the process-approximating or performing the multiplication in stages works well.

My biggest problem is keeping the digits straight in my head. I have to work at remembering the stage I'm at and the result I have come up with so far.

Chuckit · Mar 8, 2007, 10:57 AM

What Glenn said. As long as you know your times tables, doing arithmetic in your head is just a matter of being able to maintain a mental scratchpad to keep your answer-so-far. A lot of people both don't know their times tables and are easily distracted, though, so it seems hard.

Tiresias · Mar 8, 2007, 11:03 AM

^ That's what I've heard.

I live in hope.

vexborg · Mar 8, 2007, 11:32 AM

I suck at math!

Badly, very badly indeed...

SVass · Mar 8, 2007, 12:00 PM

Decimal arithmetic is obsolete. Stick to factorial base numbers. They are far more interesting. sam

mdc · Mar 8, 2007, 12:54 PM

I voted that I can do 2 digit x 2 digit. I went through Calculus and all that in school and passed with B's. So I can do math, but I hate it and find it boring.

I'm all for calculators. My one on dashboard gets the most use out of all my widgets.

Salty · Mar 8, 2007, 01:03 PM

I'm out of practice. In high school I was great at mental math cause I did it all the time... these days I'm largely estimating in my head. My math skills declined once teachers started expecting me to show all my work.

TubaMuffins · Mar 8, 2007, 01:16 PM

I picked "I am a human calculator" I have this party trick, really lame party trick, where I can convert celsius to farenheit and vice versa in my head to the exact decimal. It really gets the ladies going

finboy · Mar 8, 2007, 02:33 PM

Originally Posted by wataru

That's not math. That's arithmetic.

Exactly what I thought when I saw it. Math involves a little more abstraction.

Warren Pease · Mar 8, 2007, 03:08 PM

I can multiply ten digit numbers together in my head, as long as nine of those digits are zeros.

andi*pandi · Mar 8, 2007, 04:14 PM

Originally Posted by Chuckit

As long as you know your times tables, doing arithmetic in your head is just a matter of being able to maintain a mental scratchpad to keep your answer-so-far.

This is my problem. It's not that I don't know how to do math, like I said give me paper and I'm great, I just don't have a lot of RAM to keep placeholders and such in for the larger operations. My memory sucks.

Now, can we have a poll about being able to solve quadratic equations?