:: means average mean in mathematics.
A number system is defined as a system of writing to express numbers.
We need to find what is :: in maths
Mathematical notation consists of using symbols for representing operations, unspecified numbers, relations and any other mathematical objects, and assembling them into expressions and formulas.
: : is a mathematical notation, it is called as double colon and it is used to find the average mean.
a:b: : c:d
In the above expression it acts as an equivalent ration between a:b and c:d
Hence, :: means average mean in mathematics.
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