Worksheets(1).Select
With Selection
.Range("B21").Value = Application.WorksheetFunction.Sum("B17:B20")
.Range("C21").Value = Application.WorksheetFunction.Sum("C17:C20")
.Range("D21").Value = Application.WorksheetFunction.Sum("D17:D20")
.Range("F21").Value = Application.WorksheetFunction.Sum("F17:F20")
End With

What am I doing wrong here. I keep getting an error on this line
..Range("B21").Value = Application.WorksheetFunction.Sum("B17:B20").
I also get an error on ":" when I tried
..Range("B21").Value = Application.WorksheetFunction.Sum(B17:B20)