Question

In a simultaneous throw of a pair of dice, find the probability of getting  an even number on first

Answer 1

We know that in a single throw of two dices, the total number of possible outcomes is (6 × 6) = 36.
Let S be the sample space.
Then n(S) = 36

Let E₆ = event of getting an even number on the first throw
Then E₆ = {(2, 1) , (2, 2), (2, 3), (2, 4), (2, 5), (2, 6), (4, 1) , (4, 2), (4, 3), (4, 4), (4, 5), (4, 6), (6, 1) , (6, 2), (6, 3),
                 (6, 4), (6, 5), (6, 6) }
       i.e. n (E₆) = 18

\[\therefore P\left( E_6 \right) = \frac{n\left( E_6 \right)}{n\left( S \right)} = \frac{18}{36} = \frac{1}{2}\]