>>12907651it's just a little trick I use.
so written sheet music is divided into measures, the time signature is 4/4 there are four beats in each measure, 3/4 there are three beats in each measure, and so on. Idon't know how much of this shit you already know. anyways,
you typically read rhythms from beginning of each bar to end, each note representing a different number of beats (a quarter note is 1/4 of a 4/4 measure, and eighth note is 1/8 of a 4/4 measure, and so on)
If a rhythm is tricky though, ie you are unsure how many beats a weird written rhythm takes up, it is sometimes easier to read the back end, and then do the quick math in your head to determine the length a note or grouping of notes. Skilled musicians can do this in an instant, while reading and performing a piece of music for the first time, with fresh eyes.
I'm not sure if it's entirely mathematical but being able to quantize amounts efficiently is absolutely strengthened by musical proficiency and vice versa.