Question

Se consideră proporția x/y=7/9Determinati următoarele rapoarte :

A)2x/x+y

B)y-x/2x

C)2y/x+y

Answer 1

Explicație pas cu pas:

$\dfrac{x}{y} = \dfrac{7}{9} \iff \dfrac{x}{7} = \dfrac{y}{9} = k \\ x = 7k \\ y = 9k$

A

$\dfrac{2x}{x + y} = \dfrac{14k}{7k + 9k} = \dfrac{14k}{16k} = \dfrac{7}{8}$

B

$\dfrac{y - x}{2x} = \dfrac{9k - 7k}{14k} = \dfrac{2k}{14k} = \dfrac{1}{7}$

C

$\dfrac{2y}{x + y} = \dfrac{18k}{7k + 9k} = \dfrac{18k}{16k} = \dfrac{9}{8}$