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Problems
Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 8
2009 AMC 8
14
14
Part of
2009 AMC 8
Problems
(1)
Average Speed
Source:
11/26/2009
Austin and Temple are
50
50
50
miles apart along Interstate 35. Bonnie drove from Austin to her daughter's house in Temple, averaging
60
60
60
miles per hour. Leaving the car with her daughter, Bonnie rod a bus back to Austin along the same route and averaged
40
40
40
miles per hour on the return trip. What was the average speed for the round trip, in miles per hour?
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46
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48
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52
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<span class='latex-bold'>(A)</span>\ 46 \qquad <span class='latex-bold'>(B)</span>\ 48 \qquad <span class='latex-bold'>(C)</span>\ 50 \qquad <span class='latex-bold'>(D)</span>\ 52 \qquad <span class='latex-bold'>(E)</span>\ 54
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48
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54