Question

Trả lời 3 câu gạch chân nha mn Lưu ý TÍNH HỢP LÝ (TÍNH NHANH)

Answer 1

d: \(=\dfrac{100}{123}:\dfrac{9+7}{12}+\dfrac{23}{123}:\dfrac{27-7}{15}\)

\(=\dfrac{100}{123}\cdot\dfrac{12}{16}+\dfrac{23}{123}\cdot\dfrac{15}{20}\)

\(=\dfrac{3}{4}\left(\dfrac{100}{123}+\dfrac{23}{123}\right)=\dfrac{3}{4}\)

c: \(=\dfrac{53}{4}\cdot\dfrac{-7}{4}-\dfrac{69}{4}\cdot\dfrac{-7}{4}\)

\(=\dfrac{-7}{4}\left(\dfrac{53}{4}-\dfrac{69}{4}\right)=\dfrac{-7}{4}\cdot\left(-4\right)=7\)

Answer 2

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