Question 168113
distance equals rate * time

40(t+2)=x
70t=960-x ......where t is time traveled by the train  and t+2 is the time traveled by the bus,  and x is the distance traveled
:
add 2 equations together to eliminate the x terms
:
111t=880---->{{{highlight(t=8)}}} hours after start of train headed south(which was at 12PM) or you could say 8+2=10 hours from when the bus headed north which also produces 8PM.
:
so at 8PM they would have been 960 miles apart.