Picnic Princess posted:

I just love the sheer audacity.

Powered Descent posted:

Out of curiosity, can someone give a tl;dr of the current educational methods for doing a math problem in your head?

Powered Descent posted:

Out of curiosity, can someone give a tl;dr of the current educational methods for doing a math problem in your head?

When I was a kid, back in the Pleistocene (i.e. the late 1980s), it was the "imagine doing it on paper and try like hell to remember all the little numbers you wrote in all the various places" method which never ever worked at all for anyone. The only mental math method that ever worked for me was the "pick the nearest 'easy' numbers and then make the corrections back to the actual problem" method, which I had to make up myself because no one ever taught it. Like if it's 21*32, start with 20*30 which is easy, 600. (In case that's not easy, 10*30 is easy, then double that.) Then correct it to 21*30 = one more 30 than (20*30) which was 600, so 630, and then correct the other figure to 21*32 which is two more 21s than (21*30), so that's 630 + (21*2) = 630+42 = 672. It looks a lot more complicated in text than it is in your head, at least if your brain works along similar lines to mine. Anyway, please say they're finally teaching something like this instead of saying you're wrong, you need to imagine the algorithm we do on paper.

Captain Hygiene posted:

I heard there was no coup in Bolivia

Sagebrush posted:

And like, that's pretty much exactly how I'd do it in my head, just without vocalizing it. But when you write it out it makes people lose their minds because it seems more confusing than two minus four is 8, carry the 1, etc

bulletsponge13 posted:

Pretty much that. It teaches basic dirty estimations, then you focus in. They are taught different little tricks and poo poo that we picked up as we got older, and forced to do quick math in day to day

Platystemon posted:

There is no coup in Bolivia.

fisting by many posted:

I knew nothing about Bolivia yesterday but I assumed from all the avatarless twitter accounts supporting the coup leader that whatever was going on was a bad thing.

chitoryu12 posted:

He got temporarily banned from the UK, and the song lyrics were specifically about rape and murder. Considering how fast he's coming to Drake's defense, I wouldn't be surprised if it's another one of those "Oh, his lyrics were real thoughts" kind of things.

Powered Descent posted:

This is, no joke, one of the most hopeful things I've heard in a long time.

When I was a kid, math was presented a series of steps to be memorized and spat back out on demand. Even if you got the right answer, it was still wrong if you got to it by some other way than the exact method that was taught. It wasn't until I got to college that actually knowing what the hell any of it MEANT meant anything.

There's nothing at all wrong with knowing and applying an algorithm, as long as you know that it IS an algorithm, which is just one method of approaching a particular problem. If elementary-school math education has finally grasped this, then holy cow, I want to kiss it.

oldpainless posted:

What if you knew a guy named Al Grithims? Wouldn’t that be weird? It’d be an ice breaker that’s for drat sure.

oldpainless posted:

What if you knew a guy named Al Grithims? Wouldn’t that be weird? It’d be an ice breaker that’s for drat sure.

Sagebrush posted:

i always thought this song was great because "you can't take three from two, two is less than three, so you look at the four in the tens place" is exactly how i was taught to subtract so that made perfect sense, while subtraction with carrying remains bizarre to me.

Powered Descent posted:

The only mental math method that ever worked for me was the "pick the nearest 'easy' numbers and then make the corrections back to the actual problem" method, which I had to make up myself because no one ever taught it. Like if it's 21*32, start with 20*30 which is easy, 600. (In case that's not easy, 10*30 is easy, then double that.) Then correct it to 21*30 = one more 30 than (20*30) which was 600, so 630, and then correct the other figure to 21*32 which is two more 21s than (21*30), so that's 630 + (21*2) = 630+42 = 672. It looks a lot more complicated in text than it is in your head, at least if your brain works along similar lines to mine. Anyway, please say they're finally teaching something like this instead of saying you're wrong, you need to imagine the algorithm we do on paper.

Sagebrush posted:

For instance, to subtract 74 from 122 it might go something like

okay, so that's pretty close to subtracting 70 from 120
and that's just subtracting 7 from 12 but ten times larger, and we know that's 5
so 120-70 must be 50
then it's actually four less than that because we subtracted 74, not 70, so it's 46
but it's two more than that because we started with 122, so the answer is 48

And like, that's pretty much exactly how I'd do it in my head, just without vocalizing it. But when you write it out it makes people lose their minds because it seems more confusing than two minus four is 8, carry the 1, etc

Tiggum posted:

So, to subtract 13 from 42 by carrying, you go 2-3 is 9, carry the one so 4-1-1 is 2 and the answer is 29. Isn't that exactly what you've just described as the way you learned it? What am I missing?

Why wouldn't you just do (21x30)+(2x21) ie. 21x30 (or 21x3x10 if you want to break it down further) is 630, 21x2 is 42, 630+42 is 672. Then you don't have to remember what numbers you've added or subtracted to make the multiplication "easier".

Don't you have to go through the same process in your head as when you write it down though? I don't get how it can be simpler in your head than it is on paper. Like, I literally cannot follow your example because I have to try to hold too many numbers in my head at one time. By the time I get to line three I've completely forgotten what I'm doing.

I'm not one of those people saying that everyone should do it my way or that any way of doing it is wrong, I just don't get it. How do you even do that? How is it in any way simpler than 122-4 is 118, -70 is 48? I don't think I could even do mental arithmetic at all if I hadn't memorised the addition and multiplication tables from 2-9. I just can't hold enough numbers in my mind at one time.

Tiggum posted:

So, to subtract 13 from 42 by carrying, you go 2-3 is 9, carry the one so 4-1-1 is 2 and the answer is 29. Isn't that exactly what you've just described as the way you learned it? What am I missing?

Why wouldn't you just do (21x30)+(2x21) ie. 21x30 (or 21x3x10 if you want to break it down further) is 630, 21x2 is 42, 630+42 is 672. Then you don't have to remember what numbers you've added or subtracted to make the multiplication "easier".

Don't you have to go through the same process in your head as when you write it down though? I don't get how it can be simpler in your head than it is on paper. Like, I literally cannot follow your example because I have to try to hold too many numbers in my head at one time. By the time I get to line three I've completely forgotten what I'm doing.

I'm not one of those people saying that everyone should do it my way or that any way of doing it is wrong, I just don't get it. How do you even do that? How is it in any way simpler than 122-4 is 118, -70 is 48? I don't think I could even do mental arithmetic at all if I hadn't memorised the addition and multiplication tables from 2-9. I just can't hold enough numbers in my mind at one time.

TinTower posted:

https://twitter.com/glinner/status/1192479742051569666

MizPiz posted:

Push El Burrito posted:

And the streets are paved in cheese.

Sagebrush posted:

A while back I saw a bunch of pages from a current elementary school math textbook and it was pretty much as you describe. All simple concepts that rely on understanding numerical relationships rather than memorizing techniques by rote, but when written out longhand it seems needlessly complex because it's just hard to describe.

For instance, to subtract 74 from 122 it might go something like

okay, so that's pretty close to subtracting 70 from 120
and that's just subtracting 7 from 12 but ten times larger, and we know that's 5
so 120-70 must be 50
then it's actually four less than that because we subtracted 74, not 70, so it's 46
but it's two more than that because we started with 122, so the answer is 48

And like, that's pretty much exactly how I'd do it in my head, just without vocalizing it. But when you write it out it makes people lose their minds because it seems more confusing than two minus four is 8, carry the 1, etc

Ambitious Spider posted:

https://twitter.com/parkermolloy/status/1194245390012428290?s=21

zoux posted:

Mayoress pete can get it tbh

https://twitter.com/evolvepolitics/status/1194226294956920833

"Labor is wrong to want to forgive my tuition"
"this guy had insanely high tuition and isn't typical"
"Actually I didn't pay any tuition at all"

https://twitter.com/broderick/status/1194281530333499395

The iFunny white supremacist beat

Henchman of Santa posted:

I thought the whole point of alt-right was to make bigotry seem cool by dropping the Christian facade.

Henchman of Santa posted:

I thought the whole point of alt-right was to make bigotry seem cool by dropping the Christian facade.

Henchman of Santa posted:

I thought the whole point of alt-right was to make bigotry seem cool by dropping the Christian facade.

Accordion Man posted:

All the edgy Internet atheists that became Nazis realized that they could take advantage of the inherent white supremacy in American Fundamentalist Christianity.

Tiggum posted:

So, to subtract 13 from 42 by carrying, you go 2-3 is 9, carry the one so 4-1-1 is 2 and the answer is 29. Isn't that exactly what you've just described as the way you learned it? What am I missing?

Why wouldn't you just do (21x30)+(2x21) ie. 21x30 (or 21x3x10 if you want to break it down further) is 630, 21x2 is 42, 630+42 is 672. Then you don't have to remember what numbers you've added or subtracted to make the multiplication "easier".

Don't you have to go through the same process in your head as when you write it down though? I don't get how it can be simpler in your head than it is on paper. Like, I literally cannot follow your example because I have to try to hold too many numbers in my head at one time. By the time I get to line three I've completely forgotten what I'm doing.

I'm not one of those people saying that everyone should do it my way or that any way of doing it is wrong, I just don't get it. How do you even do that? How is it in any way simpler than 122-4 is 118, -70 is 48? I don't think I could even do mental arithmetic at all if I hadn't memorised the addition and multiplication tables from 2-9. I just can't hold enough numbers in my mind at one time.