The speed of a passenger train is 12 mph more than the speed of a freight train. The passenger train travels 290 miles in the same time it takes the freight train to travel 230 miles. Find the speed of each train.
let's say v_1 is speed of freight train, v_2 is speed of the passenger train v_2= 12+v_1 , time is "t" for the both trains is the same and you have distance of freight train s_1= 230 and distance of the passenger train s_2= 290
$\displaystyle \displaystyle v_2 = \frac {290}{t}$
$\displaystyle \displaystyle v_1=v_2 +12 = \frac {230}{t}$
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