Userform Checkbox as a value when true

Is it possible that when a user selects a checkbox on a userform i can add it into a formula on the same userform...

Example:

Checkbox1 = 0.92 if selected (true)
Checkbox2 = 20% if selected (true - note the %)
TextHours = 8 (as entered by user)
TextStaff = 2 (as entered by user)


Formulas wanted: (correct if i am seriously off course here)

Me.TextTotal = CDbl(TextStaff*TextHours*Checkbox1)

Me.TextTotal2 = CDbl(TextStaff*TextHours)*Checkbox2 =(remember as a Percent%%)


i do have set values for each of the checkboxes as required- should i do this separate with a IF/Then staement?

Another thing to think about when doing the big formula....will it see unchecked boxes as "0"