They taught you all the parts. Where they (and I’d agree most math education) failed was to connect the dots.

They taught you about these properties.

They taught you that division is just fractions and vice versa.

They taught you that x/1=x.

They taught you multiplying fractions as (numerator_a • numerator_b) / (denominator_a • denominator_b).

They taught you percentages are just “per centum”, or per hundred, or basically just a fraction “over 100”.

But these tricks, much like many other mental math shortcuts that are useful for everyday life, got glossed over or missed entirely.