Bar and bat mitzvah mean, literally, son and daughter of the commandment.. Bat mitzvah is Hebrew, while bar mitzvah, historically a much earlier ceremony, is Aramaic. The word bar is the Aramaic equivalent of the Hebrew ben (son of) .
In math, the mean is the average of a set of numbers. To determine the mean, add all numbers in a set and take this answer and divide it by how many numbers are in the set. Continue Reading.
Haskell Curry defined mathematics simply as the science of formal systems. A formal system is a set of symbols, or tokens, and some rules telling how the tokens may be combined into formulas. In formal systems, the word axiom has a special meaning, different from the ordinary meaning of a self-evident truth.