@ethant9175,
You still need to keep a running budget if you want to run a self-employed related business.
Add;
subtraction;
basic multiplication for figuring taxes (if your state or country has service related taxes akin to sales taxes);
suppose there are some degree of math knowledge in the anatomy side of the training (which I believe is a requirement to be licensed in the state of New York): on the line with premed related biology level courses, etc....
Supplementing part of certified massage therapists occupation is understanding and informing ones clients on nutrition science (to a certain degree) and all that entails... caloric and vitamin intake wise.