An "R" with two vertical lines instead of just one
Numerals are symbols used to represent numbers.
Variables
Symbols used to represent unspecified numbers or values.
A radix is the number of distinct symbols used to represent numbers in a particular base.
Variables (letters like x and y)
The letters of the Greek alphabet, Alpha, Beta, Gamma etc., etc. both upper and lower cases, were used to represent numbers
Numerals are different Numbers as for hieroglyphs are symbols used to represent numbers.
0 - 9 plus A - F
Operation symbols in mathematics are used to represent mathematical operations, such as addition (+), subtraction (-), multiplication (×), and division (÷). These symbols are used to perform calculations and denote relationships between numbers or variables.
Chemical symbols are used to represent elements.
Algebra is a part of mathematics in which letters and other symbols are used to represent numbers and quantities in formulas and equations.
Arithmetic: The mathematics of integers, rational numbers, real numbers, or complex numbers under addition, subtraction, multiplication, and division. Algebra: A branch of mathematics in which symbols, usually letters of the alphabet, represent numbers or members of a specified set and are used to represent quantities and to express general relationships that hold for all members of the set.