If a parade 2mi long is proceeding at 3 mph how long will it

If a parade 2mi long is proceeding at 3 mph, how long will it take a runner, jogging at 6 mph, to travel from the front of the parade to the end of the parade?

Apply the distance formula:
d = rt
where
d is distance
r is rate or speed
t is time
.
Let x = time it takes jogger to get to end of parade
then
3x + 6x = 2
9x = 2
x = 2/9 = 1/3 hours
or
x = 20 minutes