Average speed, and total distance traveled

AI Thread Summary
Sally's trip involves driving for three segments: 30 minutes at 80 km/h, 12 minutes at 105 km/h, and 45 minutes at 40 km/h, with a 15-minute break. To find the average speed, total distance traveled must be calculated by converting all driving times into hours and multiplying by their respective speeds. The average speed for the trip is determined to be 53.5 km/h, while the total distance traveled is 91 km. Understanding the conversion of minutes to hours is crucial for accurate calculations. The units for average speed are km/h, and for total distance, they are kilometers.
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Homework Statement


Sally travels by care from on city to another. She drives for 30.0 min at 80.0 km/h, 12.0 min at 105 km/h, and 45.0 min at 40. km/h, and she spends 15.0 min eating lunch and buying gas.
a.) Determine the average speed for the trip.
b.) Determine the total disance traveled.

Homework Equations



Vavg= total distance/time
Vavg=change in displacement/time

The Attempt at a Solution


a.) is 53.5, and b.) is 91 but I am not sure how to get them.
My friend was trying to explain it to me, and said to turn all the minutes into hours and multiple them by the speeds. I did that and got 91, but I am not sure why i had to do that.
 
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what are the units of 53.5? Give units in your answers.
 
a.) is km/h and b.) is km, i figured it out though.
 

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