Answer:
First train 364, second train 355.3
Explanation:
Let's me just say
First train = x
Second train = y
Easier to type like that
So
x + y = 719.3
they say " first train is 8.7 mph faster than that of the second train "
Therefore
x = y + 8.7
Now u have these two equations
x + y = 719.3
x = y + 8.7
Now since u know what is x, just put it in your first equation
x + y = 719.3
y + 8.7 + y= 719.3
2y = 710.6
= 355.3
Therefore the speed of the first train is
x + y = 719.3
x + 355.3 = 719.3
x =364