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3 years ago

A cross-country skier can complete a 7.5 km race in 45 min. What is the skier’s average speed? km/h

Chemistry

2 answers:

Xelga [282]3 years ago

7 0

<u>Answer:</u> The average speed of the skier is 10 km/hr.

<u>Explanation:</u>

Average speed is defined as the ratio of total distance traveled to the total time taken.

Mathematically,

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

We are given:

Total distance traveled = 7.5 km

Total time taken = 45 min = $45min\times \frac{1hr}{60min}=0.75hr$ (Conversion factor: 1 hr = 60 min)

Putting values in above equation, we get:

$\text{Average speed of skier}=\frac{7.5km}{0.75hr}=10km/hr$

Hence, the average speed of the skier is 10 km/hr.

MariettaO [177]3 years ago

3 0

10 km/h is the correct answer

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