cannot convert double to int when trying to increment another script's variable by 0.10

GlobalVariables.Valvepressure = GlobalVariables.Valvepressure + 0.1;

So, the above is my line of code. It is accessing another script where im storing a variable called “Valvepressure”. I can add full numbers to it just fine, like 1 or 2, but for some reason it throws compiler error cs0266 when i try to do the same with a decimal number.

To explain further, in my game i have 2 big valve looking things that when the player clicks on them they either increase or decrease this variable by 1. And i want to make a smaller valve that increases the Valvepressure by 0.1. so whats the problem and how do i fix it?

EDIT: i dont know how to clearify this problem, but adding “f” to the end of 0.1 does not work. also, heres the global variables script im trying to change the variable in:

public static class GlobalVariables
{
    public static int Valvepressure;
}

Well, terribly asked question… Are you using C#? If yes: you need to add ‘f’ letter after every float value 0.1f not 0.1.
If that’s not it at least tell us if ValvePressure isn’t an int value? If it is, change it to float.