Question

Harold left town driving east at 55 mph. Carol left 2 hours later driving the same route at 65 mph. How many hours after Harold left will it take Carol to catch up to Harold?

Answer 1

d = rt

Harold's Distance = 55*t
Carol's Distance = 65(t-2)

to get the time when their distance will be equal, set their distances equal to each other:
55t = 65(t-2)

55t = 65t-130
130 = 10t
t = 13

So they will run into each other 13 hours later