Final answer:
To compare P(x=9) for two distributions, we must analyze the discrete probability mass function for Distribution 1 and the continuous probability density function for Distribution 2. PMFs provide direct probabilities for discrete variables, while PDFs require evaluating a range for continuous variables.
Step-by-step explanation:
When examining the probabilities for a discrete random variable x in two distinct distributions, we specifically want to compare P(x=9). The probability mass functions (PMFs) or probability density functions (PDFs) associated with these distributions will determine the probabilities we are interested in. For Distribution 1, if it were a discrete distribution with a PMF, we would directly calculate P(x=9) by finding the value associated with x=9 in the PMF. For Distribution 2, if it's a continuous distribution, we cannot calculate P(x=9) as it would be 0, so instead, we would consider a range around 9 if needed.
Two qualities characterize a discrete PDF: each probability must be between zero and one (inclusive) and the sum of all probabilities must equal to one. These principles become relevant when assessing the probability for a discrete variable, such as in a binomial distribution, which could be applicable to Distribution 1 if x represents the number of successes in n trials with a probability p of success on each trial.
In contrast, continuous random variables, such as Distribution 2 might suggest, require a different approach where the entire probability distribution function needs to be considered. Important features of such distributions could be uniformity or exponentially declining probabilities. Fundamental features like these would help to define the likelihood of an outcome within a certain range, not at a specific point.