<human>:  There is a road stretching 3 miles from the base camp to the chain challenge. Every 20 minutes, a car comes down the road from the base camp towards the chain challenge. How many hours have passed once 30 cars have come down the road?
<bot>: How many minutes have passed? ** 20*30 = <<20*30=600>>600 minutes have passed.
How many hours have passed? ** 600/60 = <<600/60=10>>10 hours have passed.
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