On Monday, 80 - 20 = <<80-20=60>>60 people attended the game.
On Wednesday, 60 + 50 = <<60+50=110>>110 people attended the game.
On Friday, 80 + 60 = <<80+60=140>>140 people attended the game.
A total of 80 + 60 + 110 + 140 = <<80+60+110+140=390>>390 people attended the games in a week.
Therefore, 390 - 350 = <<390-350=40>>40 people more attended the games than they had expected.
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