`(5)/(7)+(y)/(35)=(4)/(5)`
`(y)/(35)=(4)/(5)-(5)/(7)`
`(y)/(35)=(4xx7-5xx5)/(35)`
`(y)/(35)=(28-25)/(35)=(3)/(35)`
`y=3`
\(\dfrac{5}{7}+\dfrac{y}{35}=\dfrac{4}{5}\)
\(\Rightarrow\dfrac{y}{35}=\dfrac{28}{35}-\dfrac{25}{35}\)
\(\Rightarrow\dfrac{y}{35}=\dfrac{3}{35}\)
\(\Rightarrow y=3\)
\(\dfrac{y}{35}=\dfrac{4}{5}-\dfrac{5}{7}\\ \dfrac{y}{35}=\dfrac{4.7-5.5}{35}\\ y=28-25\\y=3\)
\(\dfrac{5}{7}+\dfrac{y}{35}=\dfrac{4}{5}\)
\(\dfrac{y}{35}=\dfrac{4}{5}-\dfrac{5}{7}\)
\(\dfrac{y}{35}=\dfrac{28}{35}-\dfrac{25}{35}\)
\(\dfrac{y}{35}=\dfrac{3}{35}\)
\(\Rightarrow y=3\)
\(\dfrac{5}{7}+\dfrac{y}{35}=\dfrac{4}{5}\)
\(\dfrac{y}{35}=\dfrac{4}{5}-\dfrac{5}{7}\)
\(\dfrac{y}{35}=\dfrac{3}{35}\)
\(=>y=3\)

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