The Math functions action allows you to do math on values.
Although you cannot group different operations together, you can chain the same operation. In other words, you can't add two numbers and then multiply it by another number in the same function, but you can add as many numbers as you like together.
The operations available are:
Max: Given two or more numbers, return the largest number
Min: Given two or more numbers, return the smallest number
DivRem: Remainder after division (modulo operation)
Percentage: Return the percentage of a given amount