Bluebulb Projects' The Measure of Things presents:
11,000 is about three-tenths the number of Seats in Fenway Park.
In other words, it's 0.296730 times the count of Seats in Fenway Park, and the count of Seats in Fenway Park is 3.37010 times that amount.
(2013 figures; daytime capacity) (a.k.a. The Cathedral of Boston) (Boston, Massachusetts)