The Decimal, Double, and Float variable types are different in the way that they store the values. Precision is the main difference where float is a single precision (32 bit) floating point data type, double is a double precision (64 bit) floating point data type and decimal is a 128-bit floating point data type.
Float - 32 bit (7 digits)
Double - 64 bit (15-16 digits)
Decimal - 128 bit (28-29 significant digits)
More about.....Decimal vs Double vs Float
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