Question: Irwin's family went on a camping trip in the mountains. On the first day, they hiked from their car to the campsite. First, they hiked 0.2 of a mile from the car to a stream, and 0.4 of a mile from the stream to a meadow. Then they hiked 0.1 of a mile from the meadow to the campsite. How many miles did Irwin's family hike in all?
Answer: 0.7