So a car travels 2/5 mile in 1/2 minute. This means a car travels 4/5 mile in one minute. Then multiply by 60 to find how many miles it travels in 60 minutes, and you can see that you have 240/5, which is equal to 48. Therefore the speed of the car in miles per hour is 48 miles an hour. Hope this helps. Feel free to ask more questions, and ask questions about my explanation.