SOLUTION: Starting from home,James traveled uphill to the office supply store for 75 minutes for 4 mph. He traveled back home along the same path downhill at a speed of 12 mph. What is the a
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Question 747653: Starting from home,James traveled uphill to the office supply store for 75 minutes for 4 mph. He traveled back home along the same path downhill at a speed of 12 mph. What is the average speed for the entire trip from home to the office supply store and back? Found 3 solutions by stanbon, Alan3354, MathTherapy:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Starting from home,James traveled uphill to the office supply store for 75 minutes for 4 mph. He traveled back home along the same path downhill at a speed of 12 mph. What is the average speed for the entire trip from home to the office supply store and back?
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Uphill DATA:
rate = 4mph : time = 75/60 = (5/4) hrs ; distance = r*t = 4(5/4) = 5 miles
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Downhill DATA:
rate = 12 mph ; distance = 5 miles ; time = d/r = 5/12 hr
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Average speed = (total distance)/(total time) = 10 miles/[(5/4)+(5/12)] hrs
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= 10/(15+5)/12 = 10/[20/12] = 120/20 = 6 mph
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Cheers,
Stan H.
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You can put this solution on YOUR website! Starting from home,James traveled uphill to the office supply store for 75 minutes for 4 mph. He traveled back home along the same path downhill at a speed of 12 mph. What is the average speed for the entire trip from home to the office supply store and back?
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Avg speed = 2*4*12/(4+12)
= 6 mi/hr
You can put this solution on YOUR website! Starting from home,James traveled uphill to the office supply store for 75 minutes for 4 mph. He traveled back home along the same path downhill at a speed of 12 mph. What is the average speed for the entire trip from home to the office supply store and back?
Distance to supply store = , or , or 5 miles
Since distance to store is 5 miles, then distance back home = 5 miles also
Therefore, time taken to travel home = hr
Average speed = Total distance ÷ total time
Average speed = ------- ------
Average speed = ÷ ------ * ------ * ------ , or mph
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