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A car travels $8$ $km$ in the first quarter of an hour, $6$ $km$ in the second quarter and $16$ $km$ in the third quarter. The average speed of the car in km per hour over the entire journey is

  1. $30$
  2. $36$
  3. $40$
  4. $24$
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2 Answers

Best answer
8 votes
8 votes
$8$ km in the first quarter of an hour, $6$ km in the second quarter and $16$ km in the third quarter.

Total distance $= 30$ km and total time $= 3/4$. $(1/4+1/4+1/4 = 3/4)$

$\text{Average speed} = \frac{\text{Total distance}}{\text{Total time}}$

$\quad \quad \quad = \frac{30}{3/4}=30\times (4/3)=40\; km/hr$

Correct Answer: $C$
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1 votes
1 votes
(8+6+16+0)/4 =30/4 KM =7.25 km per quarter is the average.

so average speed per hour is 7.25*4 quater=30 kmps which is the option A
Answer:

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