Question

[ngo phuong thao]

tìm x : 7,5 . x : (9 - 6 \(\dfrac{13}{21}\) _{) = 2\(\dfrac{13}{25}\)}

Answer 1

[Hiiiii~]

Giải:

\(7,5x:\left(9-6\dfrac{13}{21}\right)=2\dfrac{13}{25}\)

\(\Leftrightarrow7,5x:\left(9-\dfrac{139}{21}\right)=\dfrac{43}{25}\)

\(\Leftrightarrow7,5x:\dfrac{50}{21}=\dfrac{43}{25}\)

\(\Leftrightarrow7,5x=\dfrac{43}{25}.\dfrac{50}{21}\)

\(\Leftrightarrow7,5x=\dfrac{86}{21}\)

\(\Leftrightarrow x=\dfrac{86}{21}:7,5\)

\(\Leftrightarrow x=\dfrac{172}{315}\)

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