Whats the best way to learn Mental calculation again.
>i learned it in elementary school >since we got calculators i lost my ability to do so.
i cant even add or substract in my head anymore. im not bad at math at all, but not being able to do basic operations in my head slows me down so much, because its basicly the fundation for more complex math. if i want to ad two numbers in my head i have to imagine two dices and count the dots on it like a 5yo child counting its fingers. please help me Veeky Forums it feels like im dumb if i want to multiply 8*7 and i cant do it without a calculator.
However the simple addition facts are kind of more reasoned out. Like, I don't think most people have 6+7 memorized exactly. They know it's 1 more than 6+6.
Also bump because I like this topic. What kinds of operations do you guys think everyone should be able to do without a calculator? All 2 digit addition/subtraction problems? All 2 digit multiplication? What about decimal problems? At what point is it 'bad' to be reaching for your calculator?
Zachary Wood
practice
Josiah Roberts
8*7 = 87
eazy
Connor Thomas
quite impressive honestly
Jayden Wilson
I wonder if an app like Anki would streamline that sort of thing. The base memorisation anyway.
It's a good time to self study these days.
I'm learning the guitar currently and the difference between trying to learn when I was a kid and my success with my smart phone as a teenager makes it seem 100 years have passed let alone 20. So too with language learning.
Christopher Gomez
>Common Core
Addition, subtraction, multiplication, and division up to 2 digits. Also, addition, subtraction, and multiplication of decimals up to the hundredths. Makes you look smart on a date when you get the waiter's tip right.
Nicholas Russell
>Addition, subtraction, multiplication, and division up to 2 digits
division up to two digits? You saying we should be able to do something like 28/17 in our heads? Out to how many decimal places?? How do you even do that in your head?
Hunter Lewis
Ironically the most mental calculation I do is trying to figure out what fucking percentage I got on an assignment when the points are out of weird numbers like 15 or 70.
Gabriel Kelly
Easy peasy, 28/17 is in simplest form, so it's already "calculated" t. math major :^)
Austin Price
every single digit multiplication you need to memorize but once you get to larger numbers you can just split them up
125 * 15 = 100*10 + 25*10 + 100*5 + 25*5 or = 100*15 + 25*10 + 25*5 really the less steps the better, but the less steps you do the harder it is. The more steps you do the easier it is but then it gets harder to remember what you got for each step
William Gutierrez
Be an engineer and make assumptions. 17 goes into 28 once, so it is a 1.something. 28-17 = 11, tack on a zero. 110 is a little more than 170/2, so estimate a 6. 6*17 = 102. >close enough. 110-102 = 8, tack on a 0. 80 is less than 170/2, so guess a 4. 4*17 = 68. 80-68 = 12. Repeat for how many decimals you want to take it to. Answer is ~1.75
Colton Nguyen
>mfw doing this is now commom core Brainlets will never learn how do I ace in all calculations and mental visual models.
Benjamin Ross
My bad, ~1.65. Don't know how that 7 snuck in there.
Lincoln Watson
Question here. I realized how much I suck at arithmetic and I've been practicing my multiplication I can do multiplication somewhat quicly for numbers under 30. But I clearly would be better at it if I was better at adding. Any good practice for adding? Or ways to visualize/organize the numbers in your head and stuff?
Tyler Walker
I literally don't remember my times table and have to spent 5-10 seconds multiplying anything greater than 5.
Even 8*3 takes me 5 seconds to remember. I made As in calc 1 - calc 3 before anyone calls me a brainlet.
Adrian Ramirez
there are several books on speed mathematics. I've made my son read it, he's 8. Ten minutes it and he can multiply any 2 numbers from 1 -100 within 2 or 3 seconds.
What you learn is a simple rule that applies to every number and once you learn it, you'll wonder why you weren't taught this in school. A form of it is used in the Chinese curriculum.
Jason Campbell
>you'll wonder why you weren't taught this in school. Maybe its because rote memorization is a dogshit way to learn?
Jayden Sanders
>mental maths
I imagine as if I'm writing on paper
Joshua Sanders
I'm not sure I know how to help you, but I do know that I was very intelligent as a child and math aptitude runs in my family from merchant ancestry and mechanics. My cousins and other extended family run a pretty impressive resume. If it helps you out, I'm good at proportions. If you understand proportions you understand numbers. At least that's the way I truly see it. Maybe take an Algebra 1 course on Youtube and keep pushing yourself on fractional proportions, increasing in difficulty until you reach an upper limit to numbers you can work with that you're satisfied with.
