题目
The following table summarizes the availability of trucks with air bags and bucket seats at a dealership.「huixue_img/importSubject/1564169388448419840.jpeg」What is the probability of selecting a truck at random that has either air bags or bucket seats?
选项
A.47%
B.53%
C.73%
D.86%
答案
C
解析
The addition rule for probabilities is used to determine the probability of at least oe event amng two or more events occurring. The probability of each event is added and the joint probability (if the vents are not mutually exclusive）is substracted arrive at the solution. P(air bags or buckets seats) = p(air bags)＋p(bucket seats)-P(air bags and buckets seats)=(125/220)＋(110/220)-(75/220)=0.57＋0.50-0.34=0.73 or 73%.用于概率的加法则用于确定至少一个事件或两个或多个事件发生的概率。 将每个事件的概率相加，然后减去共同的概率（如果通风孔不是相互排斥的）得出解。P(air bags or buckets seats) = p(air bags)＋p(bucket seats)-P(air bags and buckets seats)=（125/220）＋（110/220）-（75/220）= 0.57＋ 0.50-0.34 = 0.73或73％。