Multiple Blogs

I have a project the requires me to install up to 11 different blogs into one website. What I would like to know is if when installing the blogs if you have to create a different database for each blog or can they all share the same database, or would it be better to create a different database for each blog.
I theory is that it would be better to create a different database, but someone told me that would be too much work, so if anyone has any advice to throw my way please let me know.

Thank you