If you can't effortlessly multiply any 2 digit numbers together

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>normies actually believe this

>>9158563
>22 × 43 = 66
pretty sure this is not how you do double digit multiplication

>>9158575
That's the first step, 22*3

>>9158591
What's the next step in your master plan?

>>9158563
>Math is just calculation
This opinion is so reductive it makes you look like a moron.

>>9158615
22*40

protip: multiply biggest numbers first

>>9158591
>>9158666
those are bad steps, satan, should be this for mental arithmetic

20*40=800
+(2*40)=880
+(20*3)=940
+(2*3)=946

Why even bother when everyone literally carries a calculator around all day every day ?
I'm not saying it this is a good thing to completely relate on those things, but that's certainly not a necessary competence for studying math

>>9158701
20*43=860
2*43=86
860+86=946

>>9158717
now do 68*97 using that method

>>9158738
68*100 = 6800
68 * 3 = 180 + 24 = 204
6800-204=6596

>>9158738

Thread is about effortlessly multiplying 2 digit numbers, not having a singular method to always go by.

So while >>9158762 shows a different method, it's more about finding the easiest way to do it.

>>9158762
70*100=7000
70*3=210
100*2=200
2*3=6
68*97=7000-210-200+6=6596

>>9158762
>>9158772
the time you spend looking for nifty tricks to use is time you could spend doing calculations, which if you have your times table memorized is basically nothing

>>9158799
Unless you learn them by heart. There's a limited amount of 2-digit numbers, and some of the methods apply well to 90-99 (like >>9158762) and some numbers are just easy to multiply without having to go through several steps (>>9158717 vs >>9158701).

It really doesn't take a lot of effort to learn some standard multiplication tricks, and it's certainly easier than remembering a whole 90x90 table.

>>9158563
just b urself

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>>9158563
>being a human calculator autist equals to being intelligent

>>9158563
Because we've developed enough systems to omit triviality in further development of scientific or mathematic fields.

>>9158842
>humans invent calculators
>there are humans that still insist that people know how to do things in their head
They are the same type of person who says writing is bad because if you were really intelligent you would just memorize everything.