Difference between revisions of "2007 AMC 12B Problems/Problem 2"
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==Solution 2== | ==Solution 2== | ||
− | Alternatively, we can use the harmonic mean to get <math>\frac{2}{\frac{1}{20} + \frac{1}{30}} = \frac{2}{\frac{1}{12}} = 24</math> <math>\longrightarrow \boxed{ | + | Alternatively, we can use the harmonic mean to get <math>\frac{2}{\frac{1}{20} + \frac{1}{30}} = \frac{2}{\frac{1}{12}} = 24</math> <math>\longrightarrow \boxed{\textbf{(B)} }</math> |
==See Also== | ==See Also== |
Revision as of 23:36, 12 January 2018
- The following problem is from both the 2007 AMC 12B #2 and 2007 AMC 10B #3, so both problems redirect to this page.
Contents
Problem
A college student drove his compact car miles home for the weekend and averaged
miles per gallon. On the return trip the student drove his parents' SUV and averaged only
miles per gallon. What was the average gas mileage, in miles per gallon, for the round trip?
Solution 1
The trip was miles long and took
gallons. Therefore, the average mileage was
Solution 2
Alternatively, we can use the harmonic mean to get
See Also
2007 AMC 12B (Problems • Answer Key • Resources) | |
Preceded by Problem 1 |
Followed by Problem 3 |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | |
All AMC 12 Problems and Solutions |
2007 AMC 10B (Problems • Answer Key • Resources) | ||
Preceded by Problem 2 |
Followed by Problem 4 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
All AMC 10 Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.