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歡迎您訪問每日一練:有一人患了流感,經過兩輪傳染后共有100人患了流感!

每日一練:有一人患了流感,經過兩輪傳染后共有100人患了流感

更新時間:2024-01-12 12:52:16作者:貝語網校

有一人患了流感,經過兩輪傳染后共有100人患了流感,那么每輪傳染中,平均一個人傳染的人數為

A.8人

B.9人

C.10人

D.11人

試題答案

B

解:設每輪傳染中平均一個人傳染的人數為x人,

那么由題意可知(1+x)2=100,

解得x=9或-11

x=-11不符合題意,舍去.

那么每輪傳染中平均一個人傳染的人數為9人.故選B.

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