概率考题对学生的阅读理解能力、抽象思维能力、转化与化归能力有较高要求,因此,概率题成了学生数学学习与考试中“常见病”“多发病”的高危地带.一、错例评析1.因概念含混而导致的解题错误(1)想当然,错把“非等可能事件”当“等可能事件”例1在两个袋内,分别装有0,1,2,3,4,5六个数字的6张卡片,现从每个袋内任取一张卡片,求两数之和等于7的概率.错解因为所取两张卡片上两数之和共 Probability questions on the students’ reading comprehension ability, abstract thinking ability, conversion and ability to change has high requirements, therefore, the probability of the students become math learning and examinations “common disease ” “poly illness ” high risk zone First, the wrong case analysis 1 due to the concept of ambiguity caused by the problem-solving error (1) Of course, the wrong “non-possible event ” when “and other possible events ” Example 1 in two bags, respectively There are six cards with 0, 1, 2, 3, 4, and 5 numbers. Now take a card from each bag and ask for the probability that the sum of the two numbers is equal to 7. The wrong solution is because two cards The sum of the two numbers