A joint probability table is used to represent which of the following?

A joint probability table is used to represent which of the following?

• A. The range of outcomes for two uncertain variables and their probabilities
• B. The distribution of a single variable across categories
• C. The average across all outcomes
• D. The probability of the first variable only

Answer: (B)

A joint probability table shows the probabilities for every combination of outcomes of two variables. It maps each pair (x, y) to P(X = x, Y = y), so you can see how the two variables relate—whether they tend to occur together or independently, and how much probability mass sits on different pairs. If you want the distribution of just one variable, you’d sum the joint probabilities across the other variable to get a marginal distribution. The joint table isn’t about a single variable in isolation, nor is it about taking an average of outcomes; it’s about the probabilities of paired outcomes for two variables.

A joint probability table shows the probabilities for every combination of outcomes of two variables. It maps each pair (x, y) to P(X = x, Y = y), so you can see how the two variables relate—whether they tend to occur together or independently, and how much probability mass sits on different pairs.

If you want the distribution of just one variable, you’d sum the joint probabilities across the other variable to get a marginal distribution. The joint table isn’t about a single variable in isolation, nor is it about taking an average of outcomes; it’s about the probabilities of paired outcomes for two variables.