a cow and a program ape Xiao Yang every day to pick up his wife home from work. Xiao Yang at 6 o'clock on time from the company to start the car, due to possible traffic jams on the road, Xiao Yang to the wife of the company at the door of the time points evenly distributed between 6 points 20 to 6 points 30. Wife according to Xiao Yang's time to do estimates, to the company at the gate of the time points evenly distributed between 6 points 25 to 6 points 30, if the small Yang Bi wife arrived at the door of the company will be scolded, then small yang is scolded probability is ____.
- 1/4
- 1/3
- 1/2
- 2/3
- 3/4
- None of the above is not
This topic is a probability distribution problem, there are two ways to solve it.
Solution 1: can be analyzed, such as Xiao Yang in 6 points 20 to 6 points 25 to the probability of 0.5, then the wife certainly did not arrive, will not be scolded; Xiao Yang in 6 points 25 to 6 points 30 to a probability of 0.5, while the wife to at the company gate time points evenly distributed between 6 points 25 to 6 points 30, so Xiao Yang in this premise, and wife to the order is random. So the probability of being scolded is 0.5*0.5=0.25; the former 0.5 refers to Xiao Yang in 6 points 25 to 6 points 30 to this situation (
Solution 2: area method, this is not much, see figure
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The problem of the probability of getting off work--Ali pen test
