Answer:
45 mph
Explanation:
Her speed, going, is (30 miles) / (1 hour), or 30 mph. Returning, it's 60 mph. Her average speed is (30 + 30) miles divided by 1.5 hours, or 60/1.5 mph, or 45 mph. This is because it takes her 1 hour to make the outgoing trip and 1/2 hour to make the resutrn trip.