求救一個小觀念

hijenny

32.4438-!-item-!-187;#058&003962

At a certain university, the ratio of the number of teaching assistants to the number of students in any course must always be greater than 3:80.At this university, what is the maximum number of students possible in a course that has 5 teaching assistants?



(A) 130

(B) 131

(C) 132

(D) 133

(E) 134

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【答案】D

【思路】, T=5代入

400>3S,S<133.3  這個地方為什麼要變號阿? 例如 20>10 各除以五後 4>2 符號一樣沒變阿!!
so, the maximum number of students possible in the course that has 5 teaching assistants=133