my mom casually mentioned that she hates division with "two digits" and let me tell you

fuck division with two digits in the divisor

what's this bs of "you have to estimate what the next digit will be"
shit so bad i have this like, evil scientist idea of just doing ruffini instead
like you know how eg the number 5485 can be written as 5+8*10+4*10^2+5*10^3? so you can turn it into a polynomial: 5+8x+4x^2+5x^3.

The advantage is that polynomial division is much more deterministic, there's no fucking guessing :aicool: and the coefficients always have one digit
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@schappi That's how I multiply in my head. How do people who actually know maths do it?

@josemanuel i don't know what people who actually know maths do but what i do is to work my way through it using the numbers 2 and 10

for example 38*7 is 38*(10/2+2) so we have

38*10/2=380/2=190
38*2=(40-2)*2=80-4=76
190+76=190+80-4=200+80-4-10=280-10-4=270-4=266

@schappi I work better with multiples of 10. To use your own example, I would do:

30*7 = 21*10 = 210
8*7 = 56
210 + 56 = 266

If I used 5 (10/2), I would have to divide and I'm not good at that, to be honest. Same with subtraction.

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