Simplify the following text for a Grade 10 native English-speaking person.
Original: These counties are traditionally grouped into 4 provinces - Leinster ( 12 ) , Munster ( 6 ) Connacht ( 5 ) and Ulster ( 9 ) .
Simplified: The counties were in 4 provinces - Leinster ( 12 counties ) , Munster ( 6 ) Connacht ( 5 ) and Ulster ( 9 ) .