What will occur if you try to perform the following operation: int x = 10.5;

The statement int x = 10.5; results in a compile-time error because it attempts to assign a floating-point value (10.5) to a variable declared as an integer (int). In programming, specifically in languages like Java or C++, the type of data assigned to a variable must match the declared type of that variable.

In this case, the variable x is defined to hold an integer value, which means it is expected to store whole numbers without any decimal component. The value 10.5, however, is a decimal (floating-point) number. Since the decimal part cannot be appropriately represented in an integer without explicit conversion, the compiler generates an error during the compilation process, indicating that the types are incompatible.

To correctly assign a decimal value to an integer, you would need to either explicitly cast the floating-point number to an integer (e.g., int x = (int) 10.5;, which would truncate the decimal) or change the variable type to a floating-point type (like double or float), allowing it to accept decimal values. Therefore, the operation fails at compile time due to type mismatch, leading to the identified outcome.