How do I pass a boolean variable to a function?

My function has 2 parameters, and number and a boolean. When calling the function, I can set the value for the number parameter using a number variable, but I can't use a boolean variable to set the boolean parameter value. The only option I have is to manually check the box.

This means I need to check the value of by boolean variable beforehand, which seems cumbersome. Am I missing something?