Frances walks half the distance at 5km/h and ru the other half at 10km/hit the total time for her journey is 3 hours,what is the distance
since time = distance/speed,
(d/2)/5 + (d/2)/10 = 3
d = 20
check:
10/5 + 10/10 = 2+1 = 3 hrs
(d/2)/5 + (d/2)/10 = 3
d = 20
check:
10/5 + 10/10 = 2+1 = 3 hrs