Dear @robertoueti
I must give credit to the wise man of your friend, the approach as it is posed these three numbers is a perfect way to grow as a person and to apply it in our daily life adapted to the circumstances clear 3, 7, 10.
Saudação cordial
@lanzjoseg
Indeed my friend.
I think that 3,7,10 rule we can use to many things not only using investments.
Cheers!