Two planes just took off from Milwaukee wi the first plane is traveling 1.5 times as fast the second plane after traveling in the same direction for 8 hours they are 420 miles apart what is the average speed of each plane
Let's assume the speed of the second plane is "x" miles per hour.
Therefore, the speed of the first plane is 1.5x miles per hour.
After traveling for 8 hours, the first plane has covered a distance of 8 * 1.5x = 12x miles.
At the same time, the second plane has covered a distance of 8x miles.
The distance between the two planes is the difference between the distances covered by the planes, which is 12x - 8x = 4x miles.
According to the problem, the distance between the two planes is 420 miles.
Therefore, 4x = 420.
Dividing both sides of the equation by 4, we get x = 105.
Hence, the speed of the second plane is 105 miles per hour, and the speed of the first plane is 1.5 * 105 = 157.5 miles per hour. Answer: \boxed{105, 157.5}.