Redmi Note 3 Ram Question

Jan 15, 2016
Bello everyone, i have just signed up here and i bought a redmi note 3 last week. It's very beautiful, but i wonder why my 3 GB RAM is always 1.5 full also when i close every app in background. During the day, despite i continue clean the RAM it passato by 1,5/6 to 1 GB free (with no app running). Is it possible to keeo the RAM clean? I mean, with whatsapp and telegram open its strange that 1.5/1.8 GB RAM are occupied.