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MAA AMC
AMC 8
2018 AMC 8
10
10
Part of
2018 AMC 8
Problems
(1)
Harmonica
Source: 2018 AMC 8 #10
11/20/2018
The harmonic mean of a set of non-zero numbers is the reciprocal of the average of the reciprocals of the numbers. What is the harmonic mean of 1, 2, and 4?
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<span class='latex-bold'>(A) </span>\frac{3}{7}\qquad<span class='latex-bold'>(B) </span>\frac{7}{12}\qquad<span class='latex-bold'>(C) </span>\frac{12}{7}\qquad<span class='latex-bold'>(D) </span>\frac{7}{4}\qquad <span class='latex-bold'>(E) </span>\frac{7}{3}
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2018 AMC 8
AMC 8