It's almost as if multiplying a number by 6 is the same as multiplying it by five and then adding one more of the number again!!!!!!!!!!!!!!!!!!!!!!! Almost.
9 x 2 - take the second finger from the left away, youre left with 1 finger on the left and 8 on the right. 18
...
...
9 x 6 - take the sixth finger from the left away, youre left with 5 fingers on the left and 4 on the right. 54
dno if it sounds complicated, but its the easiest when you understand it.
When I was a kid I did it by taking the number right before the single number, then the second digit is what would have to be added to make the single number 10.
Like: 9x3=27
12345
3=7+10.
Your way is better though
The only trick similar to what you said that I was aware of is that to find out if a number is divisible by 3 all the numbers that you are trying to divide by 3 have to equal a number divisible by 3.
like 27. 2+7=9 .... 9 is divisible by 3
33. 3+3=6 .... 6 is divisible by 3
513. 5 +1+3=9
17283. 1+7+2+8+3=21 ....then you can go further if you feel like it. 2+1=3
and then knowing that I always knew how a number is divisible by 6. If the number is divisible by both 2 and 3 then its always divisible by 6.
I thought my school was **** because we had two 7th graders that were pregnant when i was in middle school, and less than 70% of my senior year classmates graduated.
The 10 is actually just a 1 in the tens place and a 0 in the ones place. (you're carrying the 1 just as you would when normally adding two numbers together) So we need to add those digits in the corresponding places:
6 x 10 = (5+1)0 = 60
(you have 5 tens and you add 1 ten and 0 ones)
This also works for:
6 x 12 = (6+1)2
Actually, this trick would also work for 6 times any odd number given a few tweaks:
6 x 9 = 45 + 9 = 54
(half of 9 is 4.5, or 4 tens and 5 ones. then you add 9 ones)
9 is easy to multiply in single-digit numbers.
9x1 = 09
9x2 = 18
9x3 = 27
The left number increases one, the right number decreases one.
The number you're multiplying 9 by, just subtract 9 by one less of it, and you have your second number.
And then, subtract one from the number you're multiplying 9 by, and you have the first number.
Adding the 9 ones is redundant... might as well have taken 9x6 and just knowing the answer from a different trick. Not really a trick when it is harder than the original.
In this ep. Bebe gets a lot of attention from the boys because her breasts are growing. This, of course, makes her worried that she'll get so used to the extra help and attention from boys hitting on her, that she'll become a air-headed bimbo with only looks to get what she wants. When she confesses her fears to her mom, the mother tells her not to worry because all women in her family are more than just looks. This is where Bebe makes the math question and her fears are confirmed. *flies away*
Let me start off by saying I am 17 years old, so technically I am part of the generation that gets all the **** . I am absolute **** at everything in school but math, and I took Algebra I in seventh grade. Last year I took Calculus I, and this year I'm beginning Calculus II. I've been advanced all through school, but even the kids who are special ed are required to take Algebra I and II and Geometry to get their diploma where I live, the wonderful land of Indiana. In the 80's, you would take Algebra I your senior year if you were advanced enough. We have progressed so far with the standard of our education. While my generation does get a lot of **** for being stupid, I think it should be clarified more often that the common sense and worldliness of this generation are failing, because the education system is doing its job. Which is teaching kids how to shut up and pay attention so they can learn about their future careers.
inb4 "It's all useless information", Well we very well can't teach kids from first grade how to assess career options. Those 12 years of primary schooling open us up to what we actually want to do.
I suck dick at math, pls help. just kidding, I pussied out and took college prep math my homework last night was to find percentages. I'm a senior in hs and that's my math homework
Dude you'd be amazed. I can't get into a class I want for an associate's in math but there are 20 arithmetic sections....in college...how the **** do people make it to college and not know how to add
Non-American countries seem to just take the headline "the American educational system has problems" and assume it's the education itself.
It's mostly bureaucratic problems...
How do you guys multiply / devide?
I do it by going to multiplication that I've memorized that is closest, in this case it would be 5 times 8 = 40. Then I just add 8 so it becomes 48.
With practice, I've managed to do this very fast.
dad kinda drilled it into me when I was young, so most of the table I had memorized by the time I was in middle school. It was interesting when I was the only one in class not using a calculator.
I do it in a similar way. I multiply one number either by 5 or 10 (whichever is closest to the number I'm trying to use) then multiply that by however many 5's or 10's are in the number I'm multiplying by, then add the difference.
Ex: 14X12 -- I would take 12, multiply it by 10 to get 120. Then multiply it by 4 to get 48 and then add the two.
That's how I do larger numbers as well.
I remember having this math teacher who was throwing big numbers at me infront of the class (don't take it literally please) and I'd just speed calculate it and he wasn't able to break me. So eventually he agreed to me being smart, but all I did was apply these simple tricks.
Well, if you arrived at the tricks on your own, then you are probably pretty smart. I know I was the only one in my class capable of coming up with my own way of doing things, everyone else had to use the method given to them by the teacher (which really didn't work well for me at all)
ya that looks all complex, but it seems like all you have to do is plug in the numbers into a calculator, solve for k, plug k into a second formula, and your done. if it weren't for the logarithms it'd be as simple as a system of equations.
My friend was complaining about having to learn Algebra in college. I should them what my last math class was about in college. That quit their bitching.