A car covers 4 successive 3km stretches at speed of 10kmph, 20kmph, 30kmph & 60kmph resp. Its average speed is	Choices
A) 20 km/h
B) 25 km/h
C) 30 km/h
D) 35 km/h
E) 45 km/h
20 km/hverage speed = total distance / total time   total distance = 4 * 3= 
<gadget id="calculator">4 * 3</gadget>
<output>12</output>
12 km   total time= 3/10 + 3/20 + 3/30 + 3/60   = 36/60 hr   speed =12/36 * 60= 
<gadget id="calculator">12/36 * 60</gadget>
<output>20</output>
20 kmph   20 km/hnswer : 20 km/h.
<result>A</result>
A car covers 4 successive 3km stretches at speed of 10kmph, 20kmph, 30kmph & 60kmph resp. Its average speed is