Question 1002957
The Smiths traveled to Voyageurs National Park to view the spring foliage at its peak. The driving time from their home to the park was 2 hours. For the first third of the time they spent driving to the park, the Smiths were in traffic and averaged 42 mi/h. During the second third of the 2 hours, they were able to travel at an average speed of 66 mi/h. For the final third of their trip, the Smiths traveled on local mountain roads and drove an average of 30 mi/h. 
a) What is the total distance the Smiths traveled to get to the park from their home?
42 mi/hr*(2/3)hr = 28 miles
66 mi/hr*(2/3)hr = 44 miles
30 mi/hr*(2/3)hr = 20 miles
d = 92 miles
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b)What was the average driving speed for the Smith's entire trip from home to the park? 
 My work for b:
  42+66+30=138
  138/3=46
  Answer: 46 mi/h
92 mi/2 hr = 46 mi/hr
Your method makes me uneasy, even tho your answer is correct.
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c) The Smiths traveled back home using the same route, for which the average speed limit was 60 mi/h. During their trip home, the Smiths drove at an average speed that exceeded the speed limit by 10%. How many minutes did it take the Smith's to return home from the park? Express your answer to the nearest whole number. 
 My work for c:
 60*.10=6
 60+6=66
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Their avg speed was 66 mi/hr
92 mi/66 mi/hr = 46/33 hours
(46/33)*60 =~ 84 minutes