Gaokao Math Practice Question
8. (5 分) 某路口人行横道的信号灯为红灯和绿灯交替出现, 红灯持续时间为 40 秒. 若一名行人来到该路口遇到红灯, 则至少需要等待 15 秒才出现绿灯的概 率为 $(\quad)$
- A.$\frac{7}{10}$
- B.$\frac{5}{8}$
- C.$\frac{3}{8}$
- D.$\frac{3}{10}$
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