Question 341308
They meet in 5 hours, and Jill walks at 3 km/hr. 


You need to use the formula D=VT, where D=distance, V=velocity (or speed) and T=time.


Jill:

D=VT
D=(3)(5)
D=15


So Jill travelled 15 km.


Jill and Joe started 27.5 km apart, which means that Joe must have travelled 27.5-15 = 12.5 km. We know he also walked for 5 hours.


Solve for V in the Joe equation:


V = D/T
V = 12.5 / 5
V = 2.5


So Joe is walking 2.5 km/h.