Áp dụng tính chất của dãy tỉ số bằng nhau, ta được:
\(\dfrac{x}{10}=\dfrac{y}{15}=\dfrac{z}{18}=\dfrac{x+y-z}{10+15-18}=\dfrac{25}{7}\)
Do đó: \(\left\{{}\begin{matrix}x=\dfrac{250}{7}\\y=\dfrac{375}{7}\\y=\dfrac{480}{7}\end{matrix}\right.\)
\(\left\{{}\begin{matrix}\dfrac{x}{2}=\dfrac{y}{3}\\\dfrac{y}{5}=\dfrac{z}{6}\end{matrix}\right.\)\(\Rightarrow\dfrac{x}{10}=\dfrac{y}{15}=\dfrac{z}{18}\)
Áp dụng t/c dtsbn:
\(\dfrac{x}{10}=\dfrac{y}{15}=\dfrac{z}{18}=\dfrac{x+y-z}{10+15-18}=\dfrac{25}{7}\)
\(\Rightarrow\left\{{}\begin{matrix}x=\dfrac{25}{7}.10=\dfrac{250}{7}\\y=\dfrac{25}{7}.15=\dfrac{375}{7}\\z=\dfrac{25}{7}.18=\dfrac{450}{7}\end{matrix}\right.\)
