When using binary operators with operands of different, be aware of the implicit casts.
In particular :

• If any of the operands is of a reference type, unboxing conversion is performed. Then:
• If either operand is of type double, the other is converted to double.
• Otherwise, if either operand is of type float, the other is converted to float.
• Otherwise, if either operand is of type long, the other is converted to long.
• Otherwise, both operands are converted to type int.

which means some errors could happen, especially if one of the operand is converted from a numeric type to double or float (see for more details).