Hi ,
Yes you can Create Main Master Package, In which you have to select your file and first check type of file and then set type into variable in first task
Then at lower level you can use create 3 different sequence container with 3 package execution task of control flow pointing to 3 different packages for execution.
In Prcedence constrating place expression to check type of file and on the bases of this you can decide which branch to execute.
This link will help you
http://technet.microsoft.com/en-us/library/ms140153.aspx
please let me know if you have any query.
Regards,
Mubin