Question 1122718
A freight train left Seoul and traveled east at an average speed of 55 mph. A diesel train left one hour later and traveled in the same direction but with an average speed of 60 mph. How long did the freight train travel before the diesel train caught up?
<pre>Let time freight train took to get to meeting point be T
Then time diesel train took to get to meeting point = T – 1
We then get the following DISTANCE equation: 55T = 60(T – 1)        OR          5(11T) = 5(12)(T - 1)
                                             55T = 60T – 60         OR          11T = 12T - 12
                                             55T – 60T = - 60       OR          11T - 12T = - 12 
                                            – 5T = - 60             OR          - T = - 12
T, or time freight train took to get to meeting point = {{{highlight_green(matrix(1,6, (- 60)/(- 5), OR, (- 12)/(- 1), "=", 12, hours))}}}