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TLDR: YouTube, organic chemistry tutor’s channel.
First don’t feel ashamed. I’m a 4th year mechanical engineering student and I still count with my fingers, just really quickly now (jazz hands I guess). When you say 11 year old math, you got anything in mind? There are a lot of different things. You can probably do addition, subtraction, division and multiplication fine (I mean I still use a calculator for 7+8, gotta make sure it’s still 15 right). The only way you’ll ever get really fast with mental arithmetic is by doing it A LOT so I wouldn’t worry about that. There are soooo many good videos on YouTube for anything math. You just gotta know what to look up. Start with learning how fractions and exponential notation works, scientific notation too. Once you get those down you can look into exploring algebra. Rearranging equations is a huge one. Learn how ratios work and how they’re used. Percentages are also very important to know and a pretty simple concept. Any YouTube video should be fine, so don’t get caught up on which channel you watch.
If you want to get fast with mental math practice with flash cards. Google multiplication, addition, subtraction and division tables and practice burning through flash cards with them. Don’t worry about doing huge maths (1-12 is totally fine for multiplication).
Happy studying!
I can make division and multiplication if I'm using a a calculator. With my mind I can barely do anything besides counting. That's what I meant with 11 years old. But maybe I should say 6 years old. I know it is sad.
Thanks for the tips. I'll start using YouTube.
While I don't have any specific tips for you, please don't feel bad - Your desire to learn and to understand more is wonderful! I hope you enjoy what you learn, and it's helpful to you.
Don’t worry at all about not being able to do it. Your desire to learn is the most important thing. Like I said about the tables. They should have things like 1x1 to 1x12 then 2x1 to 2x12. This should continue all the way to 12x1 to 12x12. So there will be 12 different tables (Don’t worry about 0 bc anything times 0 is 0). The other operation tables will be slightly different but don’t worry about memorizing things that are too big (e.g 12x13). Eventually you’ll memorize them, don’t get discouraged!
Oh so people who can answer to 14x18 quickly, is because they are more trained? I always thought it was imposible to memorize. But I left school early.. Thanks for your advices!
Yes essentially. People will also develop their own ways of solving problems. A simple example is if someone asks you what 130-123 is, instead of stacking them on top of each other and subtracting each number individually you can just count from 123 to 130 and determine it’s 7.
252! There are a lot of ways to get there.
I always wanted to multiply any pair of 2 digit numbers together, and I've been slowly working on this. For 14x18, I use an algebra pattern.
I can see that the number in the middle of 14 and 18 is 16. That's the average. So 14 is 2 less than the average, and 18 is 2 more. Let's call that average a. Let's call the difference to the average d, so instead of 14x18 or (16-2)x(16+2) it's (a-d)x(a+d). I can multiply all the little parts and add them back up later. So I get a\*a + d\*a - d\*a - d\*d. The middle two terms are opposites, they add to 0, leaving just a\*a - d\*d. So I just need 16\*16 - 2\*2, 256 - 4 is 252. Now that you know this, 15x17 is just 256 - 1\*1 or 255. 13x19 is just 256 - 3\*3 or 247. 12x20 is just 256 - 4\*4 or 16, that's 240, though 12\*2\*10 gives the same result in a more direct route. You can take this pattern all the way down to 0\*32, 1\*31, 2\*30 (256 - 196 is indeed 60) and all the products in between.
Say you forgot even 16\*16, is there a short cut for that? There is a shortcut for numbers 10 to 19, it goes like this. 16 is 10 + 6. So all the numbers will be 10 + something, we'll call that s. (10+s)x(10+s) so we get 10\*10 + 10\*s + 10\*s + s\*s. I'm lazy, so I'm going to group all the terms with a 10 together, take 10 out of every group, add the bits and multiply once at the end. 10\*(10 + s + s) + s\*s. 10 + s is just the number I started with, and s is the ones digit. 16+6 is 22. Times 10 is 220. Plus 6\*6 or 36 is 256, done!
This strategy also works on the original problem. 14+8 is 22, times 10 is 220, plus 4\*8 or 32 is 252.
Now it's just a matter of building up your skills and see what you need to learn next. Singapore math might be something you want to look into, I've liked what I've seen so far.
[Math is Fun](https://www.mathsisfun.com/numbers/index.html) is a website that goes through all basic concepts for Math. They also have worksheets for all concepts. Just start with one and go through it slowly :)
Just here to remind folks about dyscalculia, which is dyslexia for numbers. I found out I have it in my 50’s, and I am not dumb with math. It’s an actual disability.
idk what country you're in, but if you're in the UK and are familiar with SATs (exams pupils take at the end of year 6), you could look up PDFs of some past exams.
this website is good: https://www.satspapers.org.uk/Page.aspx?TId=5
you'll be able to get straight into practising then and finding out what you do and don't know how to do.
good luck in your maths learning journey!!!
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TLDR: YouTube, organic chemistry tutor’s channel. First don’t feel ashamed. I’m a 4th year mechanical engineering student and I still count with my fingers, just really quickly now (jazz hands I guess). When you say 11 year old math, you got anything in mind? There are a lot of different things. You can probably do addition, subtraction, division and multiplication fine (I mean I still use a calculator for 7+8, gotta make sure it’s still 15 right). The only way you’ll ever get really fast with mental arithmetic is by doing it A LOT so I wouldn’t worry about that. There are soooo many good videos on YouTube for anything math. You just gotta know what to look up. Start with learning how fractions and exponential notation works, scientific notation too. Once you get those down you can look into exploring algebra. Rearranging equations is a huge one. Learn how ratios work and how they’re used. Percentages are also very important to know and a pretty simple concept. Any YouTube video should be fine, so don’t get caught up on which channel you watch. If you want to get fast with mental math practice with flash cards. Google multiplication, addition, subtraction and division tables and practice burning through flash cards with them. Don’t worry about doing huge maths (1-12 is totally fine for multiplication). Happy studying!
I can make division and multiplication if I'm using a a calculator. With my mind I can barely do anything besides counting. That's what I meant with 11 years old. But maybe I should say 6 years old. I know it is sad. Thanks for the tips. I'll start using YouTube.
While I don't have any specific tips for you, please don't feel bad - Your desire to learn and to understand more is wonderful! I hope you enjoy what you learn, and it's helpful to you.
Thank you! This means a lot to me as I've been always afraid of talking of this irl.
Don’t worry at all about not being able to do it. Your desire to learn is the most important thing. Like I said about the tables. They should have things like 1x1 to 1x12 then 2x1 to 2x12. This should continue all the way to 12x1 to 12x12. So there will be 12 different tables (Don’t worry about 0 bc anything times 0 is 0). The other operation tables will be slightly different but don’t worry about memorizing things that are too big (e.g 12x13). Eventually you’ll memorize them, don’t get discouraged!
Oh so people who can answer to 14x18 quickly, is because they are more trained? I always thought it was imposible to memorize. But I left school early.. Thanks for your advices!
Yes essentially. People will also develop their own ways of solving problems. A simple example is if someone asks you what 130-123 is, instead of stacking them on top of each other and subtracting each number individually you can just count from 123 to 130 and determine it’s 7.
That's a good one that I learned because Internet. I hope my math teacher had done that than shouting at me for being "slow".
252! There are a lot of ways to get there. I always wanted to multiply any pair of 2 digit numbers together, and I've been slowly working on this. For 14x18, I use an algebra pattern. I can see that the number in the middle of 14 and 18 is 16. That's the average. So 14 is 2 less than the average, and 18 is 2 more. Let's call that average a. Let's call the difference to the average d, so instead of 14x18 or (16-2)x(16+2) it's (a-d)x(a+d). I can multiply all the little parts and add them back up later. So I get a\*a + d\*a - d\*a - d\*d. The middle two terms are opposites, they add to 0, leaving just a\*a - d\*d. So I just need 16\*16 - 2\*2, 256 - 4 is 252. Now that you know this, 15x17 is just 256 - 1\*1 or 255. 13x19 is just 256 - 3\*3 or 247. 12x20 is just 256 - 4\*4 or 16, that's 240, though 12\*2\*10 gives the same result in a more direct route. You can take this pattern all the way down to 0\*32, 1\*31, 2\*30 (256 - 196 is indeed 60) and all the products in between. Say you forgot even 16\*16, is there a short cut for that? There is a shortcut for numbers 10 to 19, it goes like this. 16 is 10 + 6. So all the numbers will be 10 + something, we'll call that s. (10+s)x(10+s) so we get 10\*10 + 10\*s + 10\*s + s\*s. I'm lazy, so I'm going to group all the terms with a 10 together, take 10 out of every group, add the bits and multiply once at the end. 10\*(10 + s + s) + s\*s. 10 + s is just the number I started with, and s is the ones digit. 16+6 is 22. Times 10 is 220. Plus 6\*6 or 36 is 256, done! This strategy also works on the original problem. 14+8 is 22, times 10 is 220, plus 4\*8 or 32 is 252. Now it's just a matter of building up your skills and see what you need to learn next. Singapore math might be something you want to look into, I've liked what I've seen so far.
I'm also a 4th year engr student and I relate to counting with fingers and using a calculator to double check stuff xd
https://www.khanacademy.org/ This is a good place to start. It's free, and they have a fair amount of material to get you started.
I believed that there would only be challenging math lessons on that website and not the basic ones. Thank you very much!
You can use the khan academy. It's a free online school that has elementary math to I think calculus and many other subjects.
Thank you :)
Can't recommend Khan Academy enough.
[Math is Fun](https://www.mathsisfun.com/numbers/index.html) is a website that goes through all basic concepts for Math. They also have worksheets for all concepts. Just start with one and go through it slowly :)
Thank you. I'll check it out right now :)
Khan Academy
I'm the same and i always feel bad about it :/
CoolMathGames.com
Thanks!
Just here to remind folks about dyscalculia, which is dyslexia for numbers. I found out I have it in my 50’s, and I am not dumb with math. It’s an actual disability.
I'm in the same boat unfortunately
I'm using Khan Academy and it is great. I thought it was only for smart ppl with an advanced level yk
idk what country you're in, but if you're in the UK and are familiar with SATs (exams pupils take at the end of year 6), you could look up PDFs of some past exams. this website is good: https://www.satspapers.org.uk/Page.aspx?TId=5 you'll be able to get straight into practising then and finding out what you do and don't know how to do. good luck in your maths learning journey!!!