VBA centigrade to fahrenheit - farenheit to centigrade

I have 2 labels (C and F) 2 textbox (TextC and TextF) and 2 command buttons (CtoF and FtoC)
I have put in the following code but keep getting 0 as result in both no matter what text box or command button I use or what temperature I enter.
The idea is for user to input temp in Centigrade textbox and fahrenheit to show and visa versa
I know its going to be something I've done that's silly but It has to be handed in by tomorrow and I've been playing with it for three days.

Private Sub cmdCtoF_Click()
Dim Number1 As Double
Dim Number2 As Double
Dim Answer As Double
Number1 = Val(txtC.Text)
Number2 = Val(txtF.Text)
Answer = Centigrade = 5 / 9 * Fahrenheit - 32
txtF.Text = Int(Answer)
End Sub

Private Sub cmdFtoC_Click()
Dim Number1 As Double
Dim Number2 As Double
Dim Answer As Double
Number1 = Val(txtC.Text)
Number2 = Val(txtF.Text)
Answer = Fahrenheit = 9 / 5 * Centigrade + 32
txtC.Text = Int(Answer)
End Sub