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Basic arithmetic Operations

Simple arithmetics on variables can be done using the arithmetic expression: $((expression))

A=3
B=$((100 * $A + 5)) # 305
#you just can't do like this:

C=$a+3
#Because if you try to echo it the result will be 3+3 as text

The basic operators are:

a + b addition (a plus b)

a – b substraction (a minus b)

a * b multiplication (a times b)

a / b division (integer) (a divided by b)

a % b modulo (the integer remainder of a divided by b)

a *b exponentiation (a to the power of b)