Two fair dice are thrown. What is the probability that the sum of the numbers is ?
Answer and explanation
Correct answer: B. 1/12
- Step 1: Throwing two standard dice produces possible outcomes.
- Step 2: Count the pairs that add up to : (1, 3), (2, 2), (3, 1) ( outcomes).
- Step 3: Divide favorable count by sample space size: .
Answer
1/12.
Why not the others: 1/4 overestimates the probability (); 1/9 is the probability of obtaining a sum of or (); 1/36 assumes only a single outcome yields the required dice sum.
Practise more Probability.
Free questions with an explanation for every one, and full timed JEE Main mock tests.
More Probability questions
- Two fair dice are thrown. What is the probability that the sum of the numbers is ?
- Two fair dice are thrown. What is the probability that the sum of the numbers is ?
- Two fair dice are thrown. What is the probability that the sum of the numbers is ?
- A fair die is rolled three times. What is the probability that the product of the three numbers is divisible by ?
- Urn I holds red and white balls; urn II holds red and white balls. Two balls are drawn at random from urn I and put into urn…
- A fair coin is tossed times. What is the probability that three heads occur in a row at least once?