AMC 8 1992 Problem 23
AMC8 1992 年第 23 题
概率★★★☆☆
If two dice are tossed, the probability that the product of the numbers showing on the tops of the dice is greater than 10 is
掷两个骰子，朝上面的数字之积大于 10 的概率是
- A.
- B.
- C.
- D.
- E.
正确答案 · Correct Answer
B
解析 · Solution
Solution 1
When the first dice is 1, there are no possibilities for the second dice.
When the first dice is 2, the second dice can be 6, giving one possibility.
When the first dice is 3, the second dice can be 4,5,6, giving three possibilities.
When the first dice is 4, the second dice can be 3,4,5,6, giving four possibilities.
When the first dice is 5, the second dice can be 3,4,5,6, giving four possibilities.
When the first dice is 6, the second dice can be 2,3,4,5,6, giving five possibilities.
The total number of ways for the product to greater than 10 is 1+3+4+4+5=17 and the total number of possibilities is (6)(6)=36, yielding a probability of .
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