Cint or Cdbl question

[Cassy]

here's the code for the button in question:

Private Sub btnCompute_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCompute.Click
Dim BattingAverage As Double
BattingAverage = txtHits.Text / txtBat.Text
Dim strAverage As String = "Your Batting Average is " & BattingAverage
lstAverage.Items.Add(strAverage)
End Sub


My teachers instructions says you need to convert your numeric text input to numbers using Cint or Cdbl and I'm not sure this is right. Can anyone help me?
Thank you very much