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Why is 13 minus 5 so hard for me?Follow

#1 Aug 07 2004 at 11:06 PM Rating: Decent
I mean...

11 minus 5 = 6 (easy)
12 minus 5 = 7 (a bit harder)
13 minus 5 = ...oh yeah umm....8!
14 minus 5 = 9 (easy)

I can never get 13 minus 5 or 13 minus 8 for some reason...My brain just kind of stalls. My teacher said I have a problem with my 2:3 ratios...whatever that means lol.
#2 Aug 07 2004 at 11:17 PM Rating: Excellent
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nevermind. ill be nice.

Edited, Sun Aug 8 00:17:44 2004 by Haggan
#3 Aug 08 2004 at 12:14 AM Rating: Decent
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Well, I like to focus on the five. Lets break it down. Three and two, small enough numbers, eh? Now, lets take another gander at the 13. Right off the bat, we know its 10 and three. So, the three's cancel one another out. Then its only 10 minus a two, and your left with eight. Goodluck! :รพ
#4 Aug 08 2004 at 2:58 AM Rating: Good
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Step 1. Buy a calculator

Step 2. Beat yourself to death with it

#5 Aug 08 2004 at 3:32 AM Rating: Good
Probably because you suck at math. That's as close to nice as I can get. And it took effort, too. :)

Edited, Sun Aug 8 04:33:21 2004 by TStephens
#6 Aug 08 2004 at 9:48 AM Rating: Default
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http://www.edact.com/related%5C143.pdf

Seriously, though, there's research that show's people more commonly makemistakes with subtraction that involves subtracting from odd numbers than even ones.

I could go into the technical aspects of in depth, but someone who can't handle 13-5 wouldn't be able to understand it.

Suffice to say 13-8 takes subjects longer to resolve than 14-8 in testing.
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#7 Aug 08 2004 at 11:17 AM Rating: Decent
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That clown scares me. o.O.
#8 Aug 09 2004 at 3:33 AM Rating: Good
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13's also a hard number to start with because it's a "middle" number. We tend to think and memorize numbers in sets of 10, and subsets of 5. 13, 12, 18, and 17 are in the middle of the subsets, and so are the hardest numbers for us to just grok mathmatically. It's just easier to think of numbers that are just one offset from a 5 or 10 and do the math quickly by using offsets. The farther away from a 5 or 10 number, the more thinking we have to do (and the easier it is to get confused and have to slow down and break the numbers down).

Um. We also tend to have an easier time counting "up", then down. Mentally, we can manage a number that is "one less" (19, or 14), pretty easily. We can manage "one or two more" ok as well (11, 12, 16, 17). But two less is difficult, and 3 more is difficult as well, making 13 and 18 "hard" numbers to deal with. Add in the oddness factor, and that leaves 13 as the first "worst" number we encounter (numbers in the first 10 are ok, since we tend to memorize them early on, so "3" doesn't end up being a problem, but 13 is).


The best cure for bad math skills is to play some of the more mathmatically challenging RPGs out there. It's a bit harder to find them nowadays since everthing's going to the easy d20 type systems. I used to play Champions pretty heavily back in HS. That game will cure *any* math problems you have. Today, I can still tell you whether a number is an even multiple of 5, 10, or 15 instantly, and often how many multiples just as fast (and the fractions left over if need be). Heh. And I can add up numbers on dice at ridiculous speeds at a glance.
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#9 Aug 09 2004 at 11:10 AM Rating: Good
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Wow, gbaji can tell if a number is a multiple of 5 or 10.

You're a genius!!! ;)

#10 Aug 09 2004 at 11:19 AM Rating: Default
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The best cure for bad math skills is to play some of the more mathmatically challenging RPGs out there


What's the best cure for being a pompus know it all who can't admit that he's wrong without having a massive ego breakdown?
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Disclaimer:

To make a long story short, I don't take any responsibility for anything I post here. It's not news, it's not truth, it's not serious. It's parody. It's satire. It's bitter. It's angsty. Your mother's a *****. You like to jack off dogs. That's right, you heard me. You like to grab that dog by the bone and rub it like a ski pole. Your dad? Gay. Your priest? Straight. **** off and let me post. It's not true, it's all in good fun. Now go away.

#12 Aug 09 2004 at 2:27 PM Rating: Decent
Unsigned binary.

No one really subtracts.
#13 Aug 09 2004 at 3:57 PM Rating: Decent
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Here is a sure remedy: spend more time playing EQ (prob FF) and posting in these forums.

The only thing that you really need to study is Sex Ed. Make sure to pay special attention to the chapters on abstinence and contraceptive use.
#14 Aug 09 2004 at 4:00 PM Rating: Decent
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You think your confused now. Wait until you get to Differential Equations. Then your really f*cked!
#15 Aug 09 2004 at 4:04 PM Rating: Default
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You think your confused now. Wait until you get to Differential Equations. Then your really f*cked!


Nah, theory is easy. Subtraction is hard.
____________________________
Disclaimer:

To make a long story short, I don't take any responsibility for anything I post here. It's not news, it's not truth, it's not serious. It's parody. It's satire. It's bitter. It's angsty. Your mother's a *****. You like to jack off dogs. That's right, you heard me. You like to grab that dog by the bone and rub it like a ski pole. Your dad? Gay. Your priest? Straight. **** off and let me post. It's not true, it's all in good fun. Now go away.

#16 Aug 09 2004 at 5:07 PM Rating: Decent
Quote:
Step 1. Buy a calculator

Step 2. Beat yourself to death with it


Hand of Tiger style...I see!
#17 Aug 09 2004 at 6:50 PM Rating: Good
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differential equations are actually relatively simple when you get the hang of them. Calculus is a little bit trickier... So's spelling, spelling is hard, especially difficult words like calculus.
#18 Aug 10 2004 at 8:49 AM Rating: Decent
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I don't even want to think about Calculus. ~shiver~ I barely squeezed through Calculus I and Calculus II. Differential Equations stopped my BS (Bullsh*t or Bachaelors of Science however you wish to take it) in Computer Science in its tracks.
#19 Aug 10 2004 at 9:38 AM Rating: Decent
Quote:
What's the best cure for being a pompus know it all who can't admit that he's wrong without having a massive ego breakdown?
Wow, I think we just had a breakthrough here. The first step is to recognize that you have a real problem. Facing your problem and asking for help is a big step in the right direction. I'm proud of you, Smash.
#20 Aug 10 2004 at 10:36 AM Rating: Decent
I could go into the technical aspects of in depth, but someone who can't handle 13-5 wouldn't be able to understand it.

No, go ahead and do it, please. I'm pretty interested in the info, especially if it relates to the mechanisms involved in division.

One of my favorite professors taught Computer Arithmetic, and one day when we were dividing, he told us not to feel bad as division was by far the hardest operation for anyone to perform, something like 46 actual operations take place in division. We were doing division in a negative residue number system, but still.
#21 Aug 10 2004 at 11:32 AM Rating: Default
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No, go ahead and do it, please. I'm pretty interested in the info, especially if it relates to the mechanisms involved in division.


Well, Gbaji's largely right about it. From a neuropsychology standpoint it's easier for us to manage numbers in an abstract sense that are divisable by two (eyes, hands, feet, etc.), five (fingers on a hand) and ten. There was a good deal of work done about this very thing when the US first looked at adopting the Metric system. Aside from consistency and ease of conversion, the quick simple abstract calculations are much easier. 1000g in a Kg is easier than 16oz in an Lb.

Prior sysetms of measurment, which you would have expected to have used 2's,5's and 10's were dervied from even simpler and more intuitive measurments for what a yard, or rod, or stone or whatever weighed.

Oddly, the brain is more adept ar remmebering sets of numbers in groups of three or four.

Everyone can memorize a 10 digit phone number in sets of 3-3-4 but most would be hard pressed to memorize a set of 10 didgits.

SocSec numbers are 4-2-3, credit card numbers are 4-4-4-4, etc.

There have been some studies related to the physiology of the brain that indicate the way information is stored plays an important role in this, but I'm not a nuerologist.

It's been donstrated that 46-14 is resolved by nearly everyone more quickly than 37-9 is, however.



____________________________
Disclaimer:

To make a long story short, I don't take any responsibility for anything I post here. It's not news, it's not truth, it's not serious. It's parody. It's satire. It's bitter. It's angsty. Your mother's a *****. You like to jack off dogs. That's right, you heard me. You like to grab that dog by the bone and rub it like a ski pole. Your dad? Gay. Your priest? Straight. **** off and let me post. It's not true, it's all in good fun. Now go away.

#22 Aug 10 2004 at 12:01 PM Rating: Decent
It's been donstrated that 46-14 is resolved by nearly everyone more quickly than 37-9 is, however.

That's because of the carry, one of the indivisible concepts associated with rudimentary mathematics in which I was really interested.

37-3 would be solved just as quickly as 46-14 I'd wager.

1000g in a Kg is easier than 16oz in an Lb.

This is closer to what I was talking about, I guess. But, my instict says 1000 is easier to recognize because you really only have to remember two numbers, the one and the number of zeros following it, or really only one number, since the metric system is all gloriously base ten.

The 16 oz -> 1 lb thing is really a fantastic example of how, since we were all raised with base ten, we're uncomfortable counting with anything else. If we'd been raised in hex, we'd have far less trouble with the English system of measure.

The professor I was talking about earlier was giving examples of some papers talking about this very thing. That is, the English were much better at conversions in mathematics because every day involved converting pence, threepence, sixpence, pennies, florins, crowns, shillings, and pounds back and forth.

Of course, they finally converted to a decimal based system in the early seventies because everyone got fed up with converting between the different number systems. Man, I miss his stories.
#23 Aug 10 2004 at 12:31 PM Rating: Default
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If we had eight fingers on each hand I imagine we would have been raised in hex.
____________________________
Disclaimer:

To make a long story short, I don't take any responsibility for anything I post here. It's not news, it's not truth, it's not serious. It's parody. It's satire. It's bitter. It's angsty. Your mother's a *****. You like to jack off dogs. That's right, you heard me. You like to grab that dog by the bone and rub it like a ski pole. Your dad? Gay. Your priest? Straight. **** off and let me post. It's not true, it's all in good fun. Now go away.

#24 Aug 10 2004 at 12:41 PM Rating: Decent
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540 posts
This thread is still going?! For shame Smiley: disappointed
#25 Aug 10 2004 at 4:15 PM Rating: Good
Quote:
I mean...

11 minus 5 = 6 (easy)
12 minus 5 = 7 (a bit harder)
13 minus 5 = ...oh yeah umm....8!
14 minus 5 = 9 (easy)

I can never get 13 minus 5 or 13 minus 8 for some reason...My brain just kind of stalls. My teacher said I have a problem with my 2:3 ratios...whatever that means lol.


I hope you are abourt 4 years old.

Edited, Tue Aug 10 17:17:13 2004 by FigNewton
#26 Aug 13 2004 at 10:54 AM Rating: Decent
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..*Shakes head and doesn't say a word*
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