Final answer:
The probability of choosing a black size 9 shoe from the options provided is 1 in 24, since there is one black size 9 shoe and a total of 24 different pairs of shoes.
Step-by-step explanation:
To determine the probability of selecting a black size 9 shoe, we need to consider the total number of outcomes and the number of favorable outcomes. There are three colors: tan, navy, and black. For each color, there are full sizes from 4 to 11, which means there are 8 sizes available for each color. Multiplying the number of colors by the number of sizes gives us the total number of different pairs of shoes: 3 colors × 8 sizes = 24 different pairs of shoes.
Out of these 24 pairs, only one pair is a black size 9. Therefore, the probability of randomly choosing a black size 9 shoe is the number of favorable outcomes (1) divided by the total number of outcomes (24).
The calculation for the probability is: Probability = Number of favorable outcomes / Total number of outcomes = 1 / 24