Two drivers are 420 miles away from each other when they started moving towards each other. They meet after 4 hours. What is the speed of the first car, if the second car's speed is 45 mph?

The first car is going 60 miles per hour because if the second car is going at 45 mph, after 4 hours it has already travelled 180 miles. In order for both cars to meet from a total distance of 420 miles, the first car has to travel 420 miles - 180 miles meaning that the first car travelled 240 miles. When you look back at how it took 4 hours for both cars to meet each other, this also means that the first car traveled 4 hours. So the car traveled 240 miles in 4 hours meaning that it went 240miles/4hours or 60mph.