The shortest distance they have to travel to return to their starting point is 9.4 miles.
Explanation
The joggers run 8 mile north and then runs 5 miles west. we have to calculate the shortest distance they have to travel to return to their starting point.
The distance traveled north and west respectively makes the height and base of a right angled triangle.
to find the shortest distance to the starting point, the hypotenuse has to be determined.
height h=8 miles
base b=5 miles
using pythagoras theorem
The shortest distance to the starting point is 9.4 miles