Six faces of a unbiased die are numbered with 2, 3, 5, 7, 11 and 13. If two such dice are thrown, then the probability that the sum on the uppermost faces of the dice is an odd number is

The correct answer is: 5/18

According to the probability formula, the likelihood that an event will occur is equal to the proportion of favourable outcomes to all outcomes.
Probability of event to happen P(E) = Number of favourable outcomes/Total Number of outcomes
Students can conflate "favourable outcome" and "preferred outcome." The basic formula is as follows. There are, however, additional formulas for various circumstances or events.
Here we have given six faces of an unbiased die are numbered with 2, 3, 5, 7, 11 and 13. The total on the dice's topmost faces is an odd number. Therefore, one of the two numerals on the top face is exactly 2. So the different possible combinations are:
$(2,3),(2,5),(2,7),(2,11),(2,13),(3,2),(5,2),(7,2),(11,2)$ and $(13,2)$
$Total\; combinations\; are:\; 10$
$So\; the\; probability\; that\; the\; sum\; on\; the\; uppermost\; faces\; of\; the\; dice\; is\; an\; odd\; number\; is\; 10/36=5/18.$

Here we used the concept of probability to find the answer. Probability theory is an area of mathematics that examines random events. A random event's outcome cannot be predicted before it happens, although it could take any of several different forms. So the probability that the sum on the uppermost faces of the dice is an odd number is 5/18.