He earns $80 from werewolf removal because 8 x 10 = <<8*10=80>>80
He earned $25 from vampire removal because 105 - 80 = <<105-80=25>>25
He removed 5 vampires from town because 25 / 5 = <<25/5=5>>5
There were 10 vampires because 5 / .5 = 10
There were 40 werewolves because 4 x 10 = <<4*10=40>>40
The proportion of werewolves that he removed was .2 because 8 / 40 = <<8/40=.2>>.2
The percentage of werewolves removed was 20% because 100 x .2 = <<100*.2=20>>20
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