Sub Demo()
Application.ScreenUpdating = False
Dim objOLE As Word.OLEFormat, objXL As Object
Dim R As Long, C As Long, X As Long
R = 1: C = 2
X = 100
With ActiveDocument
  With .InlineShapes(1)
    If Not .OLEFormat Is Nothing Then
      If Split(.OLEFormat.ClassType, ".")(0) = "Excel" Then
        Set objOLE = .OLEFormat
        objOLE.Activate
        Set objXL = objOLE.Object
        objXL.ActiveSheet.Cells(R, C).Value = X
        On Error Resume Next
        objOLE.Application.Quit
      End If
    End If
  End With
End With
Set objXL = Nothing: Set objOLE = Nothing
Application.ScreenUpdating = True
End Sub