Electronic Graduate Management Admission Test (e-GMAT) Practice Exam

To determine how to calculate the probability of achieving a sum of 10 with a biased die that favors odd numbers, identifying unique combinations is indeed the correct approach.

When calculating probabilities involving sums from the rolls of dice, it's important first to determine the possible combinations of die faces that can add up to the target sum—in this case, 10. By recognizing unique combinations of the die's outcomes, you establish all the different groups of numbers that result in the sum of 10.

For a biased die that favors odd numbers, it might have differing probabilities for rolling odd and even numbers. This means that not all combinations might occur with equal likelihood, but identifying those combinations is the key first step in calculating the probability.

Once unique combinations are identified, the next step involves calculating their respective probabilities based on the bias of the die. This likely means multiplying the probabilities of each individual outcome present in those combinations to find the overall probability of achieving the total sum of 10.

Understanding this process is crucial, as it lays the foundation for grasping the more complex manipulations of probabilities in biased environments, where outcomes do not follow a uniform distribution.