Multiple PCs - how many licenses for Comodo Internet Security Complete 2013

I’m thinking of buying the subject suite, and want to know if I can use it on multiple PCs - for the price listed, $39.99 (Windows 7 and XP). I have 4 windows machines in the family - one of which is for a student who is living in a different house, and am thinking of adding 2 more (laptops/notepads).
Sorry if this is a common question - I could find anything on the forum more recent that 2006 on this topic.

First of all thank you for choosing Comodo. Just one license is enough to cover your household.

Thanks for the fast answer