Question: How many female students are there in University of Pennsylvania in 2011?
SQL: SELECT CAST(T1.num_students * T1.pct_female_students AS REAL) / 100 FROM university_year AS T1 INNER JOIN university AS T2 ON T1.university_id = T2.id WHERE T1.year = 2011 AND T2.university_name = 'University of Pennsylvania'