Here is the code that can help you.
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Sub CompararCeldasLibros()
Dim numero As Double
Workbooks("AfiliadosxEdadAfiliacion_Sexo04.xls").Activate
numero = Round(ActiveCell.Value, 4)
Workbooks("AfiliadosMujeres.xls").Activate
'Debug.Print "Numero:" & numero
'Debug.Print "ActiveCell:" & Round(ActiveCell.Value, 4)
If Round(ActiveCell.Value, 4) = numero Then
ActiveCell.Interior.Color = RGB(255, 255, 0)
Else
ActiveCell.Interior.Color = RGB(255, 0, 0)
End If
End Sub
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