Question

sabe-se que os números 4,8,× e 64 são proporcionais . Determine o valo de × ​

Answer 1

$\boxed{\begin{array}{l}\sf vou~resolver~de~dois~modos:\\\sf1^{\underline a}~ supondo~que~\\\sf sejam~diretamente~proporcionais:\\\sf\dfrac{4}{\diagup\!\!\!8}=\dfrac{x}{\diagup\!\!\!\!\!\!64}\\\sf 4=\dfrac{x}{8}\\\sf x=8\cdot4\\\sf x=32\\\sf 2^{\underline a}~supondo~que~\\\sf sejam~ inversamente~proporcionais:\\\sf 4\cdot8=64\cdot x\\\sf 64x=32\\\sf x=\dfrac{32\div32}{64\div32}\\\sf x=\dfrac{1}{2}\end{array}}$