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Two dice are tossed. The probability that the total score is a prime number is:

Option :

Explanation:

Solution:
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) }
$\begin{array}{rl}& \therefore n\left(E\right)=15.\\ & \therefore P\left(E\right)=\frac{n\left(E\right)}{n\left(S\right)}\\ & =\frac{15}{36}\\ & =\frac{5}{12}\end{array}$