Little question about major system

How does the number 6 map out to the consonants ch, sh, j, zh.
It doesn’t exactly explain in the ebook, the only thing i can think to correlate it to is when I was looking back at number shapes and visualizing how the ‘6’ can look like a cherry, and obvs cherry starts with “ch”.

Maybe i’m being dumb, but correct me.

A 6 backwards is similar to a cursive j

I think the cherry mention is great too

Here’s the chart that I first learned the associations on.

Although they mention the number of downstrokes they missed the opportunity of mentioning rotating the 2 and 3 counter-clockwise to make the shape,

Also the number 8 being f,v,th is not a universal rule as some people associate th with 1