Shouldn't units in Pre calculus be ordered differently?

In Precalculus, after complex numbers there's the "Polynomials" unit, however, it teaches the binomial theorem which in order to understand must first teach "Probability and combinatorics" but is actually at the very bottom of the entire Precalculus section.

So, to promote simplicity and understanding, I request that Probability and combinatorics unit be put directly before the Polynomials unit.

Because of this problem, it caused me a fair bit of confusion in my attempt to study the Polynomials unit which could've been very simply deterred by just from different ordering.

Thank you!