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2009 AMC 12A Problem 2

Problem 2 of 25EasierAlgebra

Which of the following is equal to 1+11+11+1?1 + \dfrac{1}{1 + \dfrac{1}{1 + 1}}?

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Solution

Starting inside, 1+1=2,1 + 1 = 2, so 1+12=32.1 + \dfrac{1}{2} = \dfrac{3}{2}. Then 132=23,\dfrac{1}{\frac{3}{2}} = \dfrac{2}{3}, and 1+23=53.1 + \dfrac{2}{3} = \dfrac{5}{3}. Thus, the correct answer is C.

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Concepts: continued fraction · fraction

Problem text and solution from the LIVE past-contest archive. See also the AoPS wiki page for community solutions.