[RESOLVED] Type problem

[That Guy]

Hey, I'm working on VB 2008 and I keep having the same problem when I debug. It keeps telling me "Conversion from string "blah blah" to type 'Double' is not valid." I know that its something to do with the types and possibly ByVals? I have changed around the types many times an I keep coming up with errors while debugging. I currently have no errors on the error list and I am stumped.

What it should do first is read the input from the txtboxes on my form then calculate meal and total cost in the Processing function. then give output in the output sub. Thanks in advance.

 Private Sub btnClick_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClick.Click
        Inpt()
    End Sub

    Sub Inpt()
        Dim num1, num2, num3, num4, num5, num6, num7, calcMeal, totalCost As Double
        num1 = CDbl(org.Text)
        num2 = CDbl(dat.Text)
        num3 = CDbl(loc.Text)
        num4 = CDbl(mea.Text)
        num5 = CDbl(air.Text)
        num6 = CDbl(tax.Text)
        num7 = CDbl(tax.Text)
        Processing(num1, num2, num3, num4, calcMeal, totalCost, num5, num6, num7)
    End Sub
   
 Function Processing(ByVal num1 As Double, ByVal num2 As Double, ByVal num3 As Double, ByVal num4 As Double, ByVal calcMeal As Double, ByVal totalCost As Double, ByVal num5 As Double, ByVal num6 As Double, ByVal num7 As Double) As Double
        calcMeal = num4 * 0.5
        totalCost = num4 + num5 + num6 + num7
        Output(num1, num2, num3, num4, num5, num6, num7,totalCost, calcMeal)
    End Function
Sub Output(ByVal num1 As Double, ByVal num2 As Double, ByVal num3 As Double, ByVal num4 As Double, ByVal num5 As Double, ByVal num6 As Double, ByVal num7 As Double, ByVal totalCost As Double, ByVal calcMeal As Double)

some code omitted