Answers

2015-04-21T21:42:19+05:30
The speed of the person in case 1 is 6 Km/hr and the speed in the case 2 is 40/5= 8 Km/hr.      The average of the two speed is = 6+8 =14/2 = 7 Km/hr.
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2 3 2
2015-04-21T21:50:43+05:30
7 km/h is the average speed-
In first case -
speed- 6km/h
distance-30km
time taken-30kmph/6h=5hrs
in second case-
Distance-40km
time-5h
we know-
s=d/t
s=40km/5h
s=8km/h
total distance travalled = 30km+40 km=70km
now
average speed = (6km/h+8km/h)/2
average speed= 7km/h

check=7km/h x (5h+5h)
         = 70 km
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