Three Dice (each having six faces with each face having one number from 1 to 6) are rolled. What is the number of possible put comes such that at least one dice shows the number 2?
Reviewed by Dalvoy
UPSC Civil Services preparation
- A36
- B81
- C91Correct
- D116
Explanation
To find the number of outcomes where at least one die shows the number 2, it is easiest to subtract the outcomes where no die shows a 2 from the total possible outcomes.
Total outcomes: Since each of the three dice has 6 faces, the total number of possible outcomes is 6 times 6 times 6, which equals 216.
Outcomes with no 2: If no die shows the number 2, then each die has only 5 remaining possibilities (1, 3, 4, 5, or 6). The number of such outcomes is 5 times 5 times 5, which equals 125.
Outcomes with at least one 2: Subtract the outcomes with no 2 from the total outcomes.
216 minus 125 equals 91.
Therefore, there are 91 possible outcomes where at least one die shows the number 2. Option C is the correct answer.

Related questions
More UPSC Prelims practice from the same subject and topic.
- Prelims 2007GS1science-and-technology
Which of the following types is used by computed tomography employed for visualization of the internal structure of human body?
- Prelims 2007GS1science-and-technology
Which one of the following is the correct sequence in the order of decreasing length of the three structural parts given below of small intestine in the human body?
- Prelims 2007GS1science-and-technology
In human body, which one of the following hormones regulates blood calcium and Phosphate?
- Prelims 2007GS1science-and-technology
How do most insects respire?
- Prelims 2007GS1science-and-technology
In human being, normally in which one of the following parts, does the a sperm fertilize the ovum?
- Prelims 2007GS1science-and-technology
Which one of the following parts of human brain is the regulating centre for swallowing and vomiting?