Addition (5 + 3): 8
Subtraction (5 - 3): 2
Multiplication (5 * 3): 15
Division (5 / 3): 1.6666666666667
Modulus (5 % 3): 2
Arithmetic operators in PHP are used to perform basic mathematical operations. Addition (+), subtraction (-), multiplication (*), division (/), and modulus (%) help to carry out calculations on numbers.