Contingency Tables · Exercise 16

Use the information in the to answer the next eight exercises. The table shows the political party affiliation for various members of the U.S. Senate during two separate years when they are up for reelection.
$$\begin{array}{ccccc}\text{Up for reelection:}& \text{Democratic Party}& \text{Republican Party}& \text{Other}& \text{Total}\\ \text{Year A}& \text{20}& \text{13}& \text{0}& \\ \text{Year B}& \text{10}& \text{24}& \text{0}& \\ \text{Total}& & & & \end{array}$$

Suppose that a member of the U.S. Senate is randomly selected. Given that the randomly selected senator is up for reelection in Year B, what is the probability that this senator is a Democrat?

OpenStax, Introductory Statistics 2e · §3.4 Contingency Tables · Exercise 16