Huan jogs and walks to school each day.

Question

Huan jogs and walks to school each day. She averages 4km/h walking and 8km/h jogging. From home to school is 6 km and Huan makes the trip in 1 hr. How far does she jog in a trip?

Answer 1

Let j = time (in hours) of jogging, so 1 - j = time walking

 

Dist jogging = rate • time = 8j

Dist walking = rate • time = 4(1 - j).  Observe that the total of the two times is j + (1 - j) = 1 hour.

 

We total distances (jogging & walking): 6 = 8j +4(1 - j).

 

6 = 8j + 4 -4j          2 = 4j       j = ½ (hour) so time is equally divided between jogging & walking.

Therefore the jogging distance = 8(½) = 4 km.