The answer is:
y = 3x - 8
Find b by plugging in the point (x,y) which is (3,1).
1= 3(3)+b
1= 9 + b
-8 = b
-- The trains start moving at the same time.
-- The space between them is initially 252.5 miles.
-- They reduce the distance between them at the rate of (124.7+253.5)=378.2mph.
-- It will take them (252.5 / 378.2) = 0.6676 hour to meet.
That's 40min 3.49sec .
-- After tooting and puffing toward each other for 8 minutes, they still have <em>32min 3.49sec</em> to go before they meet each other. We're all hoping that they're on different tracks.
Volume of a cone = (1/3) x Area of the base (B) x height(h)
V = (1/3)·420·180
= 25200 mm³