An unbiased six-faced dice whose faces are marked with numbers , and is rolled twice in succession and the number on the top face is recorded each time. The probability that the number appearing in the second roll is an integer multiple of the number appearing in the first roll is
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Answer: C
Let the outcome of the first roll be and the second roll be , where .
Since the dice is rolled twice, the total number of possible outcomes in the sample space is:
We need to find the probability that is an integer multiple of (i.e., for some positive integer ). Let's list the favorable outcomes systematically for each possible value of :
- If : can be any multiple of , which are outcomes
- If : can be outcomes
- If : can be outcomes
- If : can be outcome
- If : can be outcome
- If : can be outcome
Summing these up, the total number of favorable outcomes is:
Therefore, the required probability is:
Thus, the correct option is C.
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