You can collect rubbish,plant trees, clean the area......

Ta có:\(\dfrac{2}{3}\)x=\(\dfrac{1}{2}\)y=\(\dfrac{3}{5}\)zhay x.\(\dfrac{2}{3}\)=y.\(\dfrac{1}{2}\)=z.\(\dfrac{3}{5}\)

=> \(\dfrac{x}{\dfrac{3}{2}}\)=\(\dfrac{y}{\dfrac{2}{1}}\)=\(\dfrac{z}{\dfrac{5}{3}}\)

Theo t/c mà giải

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