Try this macro:
Option Explicit
Sub DelSheets()
Dim DelSheet As Collection
Dim i As Long
Dim n As Long
Dim ws As Worksheet
Dim ws2 As Worksheet
Dim Counter As Long
Dim Str As String
Application.DisplayAlerts = False
Set DelSheet = New Collection
Str = "The following sheets have been deleted:"
For Each ws In Worksheets
Counter = 0
For Each ws2 In Worksheets
If Left(ws2.Name, Len(ws2.Name) - 1) = Left(ws.Name, Len(ws.Name) - 1) Then
Counter = Counter + 1
End If
Next
If Counter = 1 Then
DelSheet.Add ws.Name
End If
Next
If DelSheet.Count > 0 Then
For i = 1 To DelSheet.Count
Sheets(DelSheet(i)).Delete
Str = Str & vbNewLine & DelSheet(i)
Next
MsgBox Str
End If
Application.DisplayAlerts = True
End Sub