Greg drives 30 miles from his workplace to the farmer's market. After buying his groceries at the farmers market, he drives home. To get home, he travels for 30 minutes at 20 miles per hour. How many miles in total does Greg travel? Let's think first. Chain of thought:
We must first convert minutes to hours, so 30 minutes * (1 hour / 60 minutes) = 0.5 hours. The number of miles Greg travels on his trip home is 0.5 hours * 20 mph = 10 miles. The total miles Greg travels is 10 + 30 = 40 miles.
Therefore, the answer is 40.