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A car travels at a constant speed of 30 km/hr for 50 km and 40 km/hr for the next 10 km. What is the average velocity of the car for the entire journey? A) 32 km/hr B) 35 km/hr C) 38 km/hr D) 40 km/hr

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Answer:

To find the average velocity, we use the formula:

\[ \text{Average Velocity} = \frac{\text{Total Displacement}}{\text{Total Time}} \]

Since the car travels at a constant speed, the total time can be calculated by adding up the time taken for each segment.

Time taken for the first 50 km: \( \frac{50 \text{ km}}{30 \text{ km/hr}} = \frac{5}{3} \text{ hr} \)

Time taken for the next 10 km: \( \frac{10 \text{ km}}{40 \text{ km/hr}} = \frac{1}{4} \text{ hr} \)

Total time: \( \frac{5}{3} + \frac{1}{4} = \frac{19}{12} \text{ hr} \)

The total displacement is the total distance traveled, which is 60 km.

Average Velocity: \( \frac{60 \text{ km}}{\frac{19}{12} \text{ hr}} \approx 38.95 \text{ km/hr} \)

Rounding to the nearest option, the answer is C) 38 km/hr.

Step-by-step explanation:

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