Table: list of craters on venus
Question: What is the probability that a randomly selected crater from the list has a diameter of at least 20 km?
Step 1 (Operation, Indexing): diameter (km)
Step 2 (Operation, Grouping): diameter (km)
Step 3 (Reasoning, Grounding): probability of randomly selected crater, percentage
Step 4 (Reasoning, Arithmetic): ratio, diameter less than 20km
Answer: 0.6