Question

Cho x;y;z thõa mãn: \(\frac{3x}{4}=\frac{y}{2}=\frac{3z}{5}\)và y-z =15. giá trị x+y+z=...

Answer 1

+) \(\frac{y}{2}\) = \(\frac{3z}{5}\) \(\Rightarrow\frac{y}{2}=\frac{z}{\frac{5}{3}}=\frac{y-z}{2-\frac{5}{3}}=\frac{15}{\frac{1}{3}}=45\)

+) \(\frac{3x}{4}=\frac{x}{\frac{4}{3}}\)

\(\Rightarrow\left\{\begin{matrix}\frac{x}{\frac{3}{4}}=45\Rightarrow x=27\\\frac{y}{2}=45\Rightarrow y=90\\\frac{z}{\frac{5}{3}}=45\Rightarrow z=75\end{matrix}\right.\)

Gía trị x + y + z = 27 + 90 + 75 = 192