55mph.
you can solve it using the equation distance=speed x time
your total distance is 714, and you have 2 trains, one traveling some speed, x, and one traveling x+8, both traveling for 7 hours.
your equation would look like this

and you can then solve for x, which would be 47. this is the speed of the slower train, but 47+8=55 with give you the speed of the faster train.
Answer:lobster
Step-by-step explanation:
You do 304 subtract 217 which equals 87
7x - 6 = 85
7x = 85 + 6
7x = 91
x = 91/7
x = 13......Mrs. Reno is thinking of 13...thats just creepy