Any low-code backend builder implies there is code being written. Functions/methods like the example you have are literally part of most Math libraries in whatever language is in the backend - Ruby, Python, PHP, Java, Perl, etc.

You should consider finding business problems that need solving with no/low code solutions which will lead you to what might need to be built. For example, if I'm building a no-code app for a Realtor persona then I might want various features that do a mathematical average.