题目
The maximum possible score in an exam is N while the pass mark is 35% of N. A student obtains 42 marks, but he falls short of the pass mark by 40%. What is the value of N ?
解析
42 比 $N$ 的 35% 少 40%。
因此 $42 = (100\%-40\%) \times (35\% \times N) = 60\% \times 35\% \times N = 21\% \times N$
由此可得,若 $42 = 21\% \times N$,则 $N$ 的 100% 为 $42\times100\div21 = 200$
答案:C - 200