Softface posted:

joining this "sounds like you might die" group is the best thing i ever did.

Besesoth posted:

Reply with "have you tried LSD?".

Away all Goats posted:

Mister Mind posted:

Now do, "The average is 5.5? I thought it was 4. This is very unsettling."

The Saddest Rhino posted:

IM DELETING YOU, ELLIOT RODGER!😭👋 ██]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]] 10% complete..... ████]]]]]]]]]]]]]]]]]]]]]]]]]]] 35% complete.... ███████]]]]]]]]]]]]]]]] 60% complete.... ███████████] 99% complete..... 🚫ERROR!🚫 💯True💯 supreme gentlemen are irreplaceable 💖I could never delete you Elliot Rodger!💖 Send this to ten other 🎩supreme gentlemen🎩 who give you 💦cummies💦 Or never get called 💯supreme💯 again❌❌😬😬❌❌ If you get 0 Back: no girlfriends for you 🚫🚫👿 3 back: you're supreme💯💦 5 back: you're Elliot Rodger's murder victim😵👼💦 10+ back: the supreme gentleman😛😛💕💕💦👅👅

Ravenfood posted:

For small numbers, its really not, but the method you describe as "common core" is a lot easier to scale up to larger numbers and a lot of people do it anyway without realizing. You can apply it to multiplication too, which I think is the draw. Adding (9x2) to something can be really quickly done by adding 10x2 and then subtracting 2, for instance. I found it a lot easier to do mental math when I started going to nearest tens/hundreds/whatever and working out the differences instead of just memorizing my multiplication tables. That's when math clicked for me in 3rd grade. And its not like they can't just use memorization tables either, its a different way of teaching things that might work better for some students, like me. But one thing I liked is that, especially for multiplication, once I'd left my memorized grid, it was a lot easier to multiply whatever to the nearest 5 or 10 and then subtract the difference, so 8x232 (or whatever) becomes [(10x232)-(2x232)]. If you teach young kids to be comfortable manipulating numbers instead of just memorizing their grid, maybe they'll understand math a little better instead of treating it like some weird black box.

How do you mentally calculate tips? I'll bet you do 10%, then halve that and add it to the original value instead of immediately multiplying your bill by 0.15. I think the principle is, I think, the same, but applied to addition instead.

Turtlicious posted:

This just blew my loving mind, and I am 24

Bobby Digital posted:

Like with that 8x232 example, I’ll show them how you could do it as 8x200 + 8x30 + 8x2, all of which are extremely doable mentally, and they’re just

Who What Now posted:

Try doing 45,687-39,898 on paper and watch as it turns into seven or eight steps of "borrowing" and poo poo like that.

Bobby Digital posted:

45,687-39,898
45,789 - 40,000
5,789

Dejawesp posted:

And you can just feel all the fedoras sage nodding at this.

They see a simple message like "don't hit women" and their brains go at it like it's some puzzle and the solution is to find a way to hit women and out comes the "well actually"

Tiggum posted:

Except then you've got to remember the three answers and add them together. If you do it the other way around you can just do it all at once.

8x2 is 16, carry the one. 8x3+1 is 25, carry the two. 8x2+2 is 18, so the answer is 1856.

It's one step. Or 5 if you count each digit as a separate step, I guess.

7-8 is 9, carry the one. 8-9-1 is 8, carry the one. 6-8-1 is 7, carry the one. 5-9-1 is 5, carry the one. 4-3-1 is 0. Answer is 5789. If you're doing it on paper you just write the final number down in reverse as you go.

You first have to waste time working out 40,000-39,898 and 45,687+102 though.

Volcott posted:

I am 100% going to punch a woman if she tries to gut me like a fish, though.

Tiggum posted:

Except then you've got to remember the three answers and add them together. If you do it the other way around you can just do it all at once.

toanoradian posted:

Hey, smart math guys, I have a question:

Imagine multiple sets of multiple buttons. Mark the sets A, B, C, and so on. Mark the buttons with the set they're in, plus a number, so A1, A2, A3, B1, B2, and so on.
You can press the button marked "1" in any order, but for buttons with number higher than 1, you have to have pressed all buttons of lower numbers. So you can only press A3 if you have pressed A1 and A2.
You can choose which set to press any order you like, so you can press the B buttons first, then the D buttons, then the A buttons, as long as it follows the above rule. So if you have pressed A2 and D3, you can press D4, then B1, A3, B2, C1 and so on.
You can't repress a button.

How many different ways can you press 5 sets of 3 buttons?

Picnic Princess posted:

Chances are guys who gleefully want to use feminism as a get out of jail card to beat up women don't actually see women as people occupying the same level as men.

Picnic Princess posted:

Chances are guys who gleefully want to use feminism as a get out of jail card to beat up women don't actually see women as people occupying the same level as men.

Bobby Digital posted:

Multiply the number of options for each button together, and there’s your answer.

Weatherman posted:

What if you hit a spergling who's sperging out about maths? Would that be schadenfreude? What if they were standing on a treadmill?

toanoradian posted:

This is the result if you exhaust the sets first, which would be (5!)^3. If you instead chose to exhaust the 1s first, then the 2s, then the 3s, what you'll have is (5!) * (5^10), which is a vastly larger number than (5!)^3.

Hate Fibration posted:

if you think Common Core is unnecessarily complex your mathematics teachers have failed you.

Untrustable posted:

All this math chat is killing me. I almost failed out of high school because I can't do algebra. My brain refuses to understand it. I don't know what the deal is but no amount of tutors and private lessons could get me through basic algebra 1. I can't do most math in my head which is funny because I run a business and I'm great at business math. That's actually what saved me from dropping out of school. I took a semester of business math and a semester of geometry to get the credits I needed to graduate. It's shameful but I can't even do long division without a calculator. I can't multiply past 1 digit numbers without a calculator. Example: 22X57...couldn't even guess at what that might be without a calculator. I excelled at every other subject but my brain outright rejects math. It sucks in a way because I always wanted to be an engineer or an architect but there's too much math involved. I like the business I'm in now but I feel like I missed out by not knowing math.

Mazerunner posted:

think of it like, break it down or round it off into numbers you can work with more easily.

so 22x57: round it up to 22x60. That's a bit nicer, right? Just gotta remember you have three 'extra' 22s. So 22 x 60 - 3x22.

3 x 22 is pretty simple, we'll just solve it for 66. You could break it down into 3 x 20 + 3 x 2 if you had to though.

So at this point we are just remembering three numbers: 22 needs to be multiplied by 60, and we have to subtract 66.

Probably you could quickly or intuitively figure it's 1320 - 66, but we'll break down 22 into 20 + 2, so it becomes 20 x 60 = 1200, + 2 x 60 = 120.

1200 + 120 - 66 = 1254.

Hell, depending on how exact you need to be, you could just say gently caress it and go with 20x60 = 1200 and you're not that far off if all you need is a quick estimate for a bit, until you can get a calculator for the precise answer.

And yes, Tiggum, you could cross multiply:

2 x 7 = 14
2 x 50= 100
7 x 20 = 140
20 x 50 = 1000

Add 'em all up for 1254. But at each point you still have to remember the answers you calculated earlier- by the end you're trying to hold each line's answer in your head while doing the next, or add them up on the fly as you go. Some people can do that, some can't, which is where alternative methods are useful.

Especially if you start getting into even bigger numbers. If you were trying to multiply two 6 digit figures, the amount of work required to cross multiply goes up heavily, while the common core process scales much better.

Untrustable posted:

I'm having uncomfortable flashbacks to high school. I'm reading what it says and going over it again and again and I'm getting that same old feeling of hopeless frustration I felt through school when a tutor tried to explain it to me. I know there are words, explaining numbers, but I just can't figure it out. Even step by step I can't figure it.

Edit: I'm just seeing kindly old Mr. Bumgardner shaking his head and asking why I can't understand. It's a weird feeling.

Picnic Princess posted:

I think I found a whole new realm of social media idiocy: rating a business while it's still under construction. Especially when the building burns down during construction. Oops.

Picnic Princess posted:

I think I found a whole new realm of social media idiocy: rating a business while it's still under construction. Especially when the building burns down during construction. Oops.

Picnic Princess posted:

I think I found a whole new realm of social media idiocy: rating a business while it's still under construction. Especially when the building burns down during construction. Oops.