Two dice are rolled find the probability that the sum is equal to 4

There are totally 12 numbers on two dices. 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6

The possibility of getting the sum of 4 from two dices are

1 + 3
3 + 1
2 + 2
2 + 2

There are totally 36 different possibilities of getting a sum of numbers from both dices.
There are 8/36 possibilities to get a sum of 4, which simplifies to 2/9

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