[roceasta]

Have you noticed that most adults don't know what nine times seven is? If you ask them on the street they'll mostly either get it wrong or tell you quite rudely to go away. This is despite (and because of) a decade of grind at school. Or have you noticed that people are unable to hold a conversation in a foreign language despite years of 'study' in a classroom? Whereas an enthusiastic individual can pick up basic conversation for themselves in a matter of months.

This is because coercion in education is: (1) painful, (2) prophetic, (3) it doesn't work!

What happens in real life is that if somebody needs to know something because they are keen to do something else then they will learn it efficiently, 'just in time' and precisely to the extent needed. Assuming their creativity is relatively intact...

https://www.youtube.com/watch?v=iG9CE55wbtY

[ajuc]

Not really (but then I never asked random people to multiply for me :) ).

But I can kinda understand why, you almost never have to multiply 9*7 by hand. If you're doing algebra or any symbolic calculations you rarely use digits other than 0-4.

In real world Benford's law + usual rounding greatly reduces the need to multiply by 7 or 9 (or 8 for that matter).