Question

( 7 . 13 + 8 . 13 ) / \(\left(9\dfrac{2}{3}-y\right)\) = 39

Answer 1

\(\dfrac{7.13+8.13}{9\dfrac{2}{3}-y}=39\)

=> \(\dfrac{13.\left(7+8\right)}{\dfrac{29}{3}-y}=39\)

=> \(\dfrac{13.15}{\dfrac{29}{3}-y}=39\)

=> \(\dfrac{195}{\dfrac{29}{3}-y}=39\)

=> \(\dfrac{29}{3}-y=5\)

=> y = \(\dfrac{14}{3}\)

@Bùi Thị Phương Anh

Answer 2

\(\dfrac{7.13+8.13}{9\dfrac{2}{3}-y}=39\)

\(\Leftrightarrow\dfrac{13\left(7+8\right)}{\dfrac{29}{3}-y}=39\)

\(\Leftrightarrow\dfrac{13.15}{\dfrac{29}{3}-y}=39\)

\(\Leftrightarrow\dfrac{195}{\dfrac{29}{3}-y}=39\)

\(\Leftrightarrow\dfrac{29}{3}-y=39\)

\(\Leftrightarrow y=\dfrac{14}{3}\)

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