MathDB
Easy Function

Source: 1968 AHSME Problem #4

August 31, 2011
functionAMC

Problem Statement

Define an operation * for positve real numbers as ab=aba+ba*b=\dfrac{ab}{a+b}. Then 4(44)4*(4*4) equals:
<spanclass=latexbold>(A)</span> 34<spanclass=latexbold>(B)</span> 1<spanclass=latexbold>(C)</span> 43<spanclass=latexbold>(D)</span> 2<spanclass=latexbold>(E)</span> 163<span class='latex-bold'>(A)</span>\ \frac{3}{4} \qquad <span class='latex-bold'>(B)</span>\ 1 \qquad <span class='latex-bold'>(C)</span>\ \dfrac{4}{3} \qquad <span class='latex-bold'>(D)</span>\ 2 \qquad <span class='latex-bold'>(E)</span>\ \dfrac{16}{3}