A man completes a certain journey by a car. If he covered 30% of the distance at the speed of 20kmph. 60% of the distance at 40km/h and the remaining of the distance at 10 kmph, his average speed is:
A.25 km/h
B.28 km/h
C.30 km/h
D.33 km/h
Answers
Answered by
0
Let the total distance be 100 km.
Average speed = total distance covered/ time taken;
= 100/[(30/20)+(60/40)+(10/10)];
= 100/[(3/2)+(3/2)+(1)];
= 100/[(3+3+2)/2]
= (100*2)/8
= 25 kmph.
Average speed = total distance covered/ time taken;
= 100/[(30/20)+(60/40)+(10/10)];
= 100/[(3/2)+(3/2)+(1)];
= 100/[(3+3+2)/2]
= (100*2)/8
= 25 kmph.
Similar questions