Two dice are tossed. The probability that the total score is a prime number is:
[A].
| 1 |
| 6 |
[B].
| 5 |
| 12 |
[C].
| 1 |
| 2 |
[D].
| 7 |
| 9 |
Answer: Option B
Explanation:
Clearly, n(S) = (6 x 6) = 36.
Let E = Event that the sum is a prime number.
| Then E | = { (1, 1), (1, 2), (1, 4), (1, 6), (2, 1), (2, 3), (2, 5), (3, 2), (3, 4), (4, 1), (4, 3), (5, 2), (5, 6), (6, 1), (6, 5) } |
n(E) = 15.
| P(E) = | n(E) | = | 15 | = | 5 | . |
| n(S) | 36 | 12 |
