Simplify the following text for a Grade 8 native English-speaking person.
Original: Christ Church has produced thirteen British prime ministers , which is equal to the number produced by all 45 other Oxford colleges put together and more than any Cambridge college ( and two short of the total number for the University of Cambridge , fifteen ) .
Simplified: Christ Church has produced thirteen British prime ministers . This is equal to the number produced by all 45 other Oxford colleges put together , and two short of the total number for the University of Cambridge ( fifteen ) .