<human>:  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?
<bot>: How many minutes are in an hour? ** We must first convert minutes to hours, so 30 minutes * (1 hour/60 minutes) = <<30*(1/60)=0.5>>0.5 hours
How many miles does Greg travel on his trip home? ** The number of miles Greg travels on his trip home is 0.5 hours * 20 mph = <<0.5*20=10>>10 miles
How many miles does Greg travel in total? ** The total miles Greg travels is 10 + 30 = <<10+30=40>>40 miles
#### 40