There were over nine hundred people in the audience.
Tips
grammar
Just the cardinal number 900 - 九 (nine) + 百 (hundred). To talk about 'nine hundred X', insert a measure word: 九百个人 (900 people), 九百块钱 (900 yuan). Note: when the number stands alone before 块/yuan in casual speech, the 钱 can be dropped.
