How do muggles get admitted to Hogwarts?

[ghinghapuss]

No: HPFGUIDX 79825

Boris said:
But this raises the question of how 
does the quill know what muggle is going to be a witch or wizard?  
How did the quill know the day Hermione was born that she could be a 
witch?  Can muggles learn to be a wizard or witch, or must they be 
born that way?  Are some muggles born with a magic gene?  Does this 
mean Lilly and Hermione were really witches from birth, although 
they had muggle parents?

Now me:
All witches and wizards in the Harry Potter universe are born that 
way.  Sometimes to muggle parents, sometimes to magical parents, 
sometimes to mixed parents and sometimes magical parents give birth 
to a squib.  Whether it's by pure chance or genes or divine 
intervention...who knows.  But you cannot learn to be a witch or 
wizard. 
Mandy