Question

Ben start walking along a path at 2 mi/h. one and a half hours after ben leaves, his sister jen begins to jogging along the same path at 7mi/h. how long (in hours) will it be before jen catches up to ben.

Answer 1

Let t be the time traveled by Ben

2 mph * t = S where S is the distance traveled

7 mph * (t - 1.5) = S same distance as Ben

2 t = 7 t - 10.5

5 t = 10.5

t = 2.1 where t is in hours

So Ben travels for 2.1 hrs

Jen travels for 2.1 - 1.5 = .6 hrs before catching Ben

Check:

2 * 126 min = 7 * 36 min

252 = 252