Question: Van Helsing gets paid by the town to remove all the vampires and werewolves. He gets $5 per vampire and $10 per werewolf. He removes half the vampires and removes 8 werewolves, and earned $105. There were 4 times as many werewolves as vampires. What percentage of the werewolves did he remove? Think carefully first, then make a decision:
He earns $80 from werewolf removal because 8 x 10 = 80. He earned $25 from vampire removal because 105 - 80 = 25. He removed 5 vampires from town because 25 / 5 = 5. There were 10 vampires because 5 / .5 = 10. There were 40 werewolves because 4 x 10 = 40. The proportion of werewolves that he removed was .2 because 8 / 40 = .2. The percentage of werewolves removed was 20% because 100 x .2 = 20. So the answer is 20.