How do I set value of datagridview row based on another row

Quote:

I had this problem in a datagridview row where i have 3 columns. Datagridview data is loaded from query in vb.net. Below is the scenario:

Column1 Column2 Column3
3 75 3
3 76 3
3 IP 0
3 NFE 0

If "Column2" cells contains "IP" or "NFE", "Column3" value is "0" BUT
If "Column2" cells contains "75" or "76", "Column3" value is "EQUAL" to "Column1"

I got this code where i used "For Each" loop;

BUT sad to note that returns me this ERROR;

"Conversion from string "IP" to type 'Double' is not valid."

Please help me with this problem thank you.

Private Sub DGVGRADES_CellValueChanged(sender As Object, e As DataGridViewCellEventArgs) Handles DGVGRADES.CellValueChanged
        For Each row As DataGridViewRow In DGVGRADES.Rows
            If row.Cells(4).Value >= 75 Then
                row.Cells(0).Value = row.Cells(3).Value
            ElseIf row.Cells(4).Value.ToString <= 3 Then
                row.Cells(0).Value = row.Cells(3).Value
            ElseIf row.Cells(4).Value < 75 Then
                row.Cells(0).Value = 0
            ElseIf row.Cells(4).Value = "IP" Then
                row.Cells(0).Value = 0
            End If
        Next
    End Sub