Question

fraçao equivalente a 39/91 sendo 20 a soma do numerador com o denominador

Answer 1

$\left\{\begin{matrix}\dfrac xy=\dfrac{39}{91}\\x+y=20\end{matrix}\right.\\\\ *x=20-y\\\\\dfrac{20-y}{y}=\dfrac{39}{91}\\\\39y=1820-91y\\\\130y=1820\\\\y=14 x=6\\\\\boxed{\dfrac{6}{14}}$