Understanding numeric data type conversions in DAX
This article describes how DAX automatically converts data types in arithmetic operations. These small details can cause and explain differences in results when using the same operations in other languages.
A DAX expression usually does not require a cast operation to convert one data type into another. You can use a string in a numeric expression and the string is automatically converted into a corresponding number, as long as the string is a valid representation of a number. The same automatic conversion takes place between different numeric data types. In this case, the result of the expression might not be obvious; indeed, the differences in the rounding of decimals between different data types might cause different results, depending on the data type of the operands and on the operators used in the expression.