Problema Solution
at 2:00pm a train left a station traveling east at r mi/h. At 3:00pm a second train headed west from the station at a rate 20 mi/h faster than the first. How far apart were the trains at 5:00pm
Answer provided by our tutors
let
v1 = r mi/h the rate of the train going east
v2 = r + 20 mi/h the rate of the train going west
at 5pm
the first train would have traveled 5pm - 2pm = 3 hours
the second train would have traveled 5pm - 3pm = 2 hours
we need to find the distance between the trains
since they are heading in opposite directions we need to find the sum of each of their distances passed
r*3 + (r + 20)*2 = 5r + 20 mi
at 5pm the trains were (5r + 20) miles apart.