Question

tính giá trị biểu thức ^{_{\(\dfrac{2}{3}+\dfrac{1}{3}.\left(-\dfrac{4}{9}+\dfrac{5}{6}\right):\dfrac{7}{12}\)}}

Answer 1

\(=\dfrac{2}{3}+\dfrac{1}{3}.\dfrac{7}{18}.\dfrac{12}{7}\)

\(=\dfrac{2}{3}+\dfrac{7.3.2.2}{3.7.3.2.3}\)

\(=\dfrac{2}{3}+\dfrac{2}{9}=\dfrac{8}{9}\)

Answer 2

TICK CHO MÌNH NHÉ

Giải:

\(\dfrac{2}{3}\) + \(\dfrac{1}{3}\) . (\(-\dfrac{4}{9}\) + \(\dfrac{5}{6}\) ) : \(\dfrac{7}{12}\)

 = \(\dfrac{2}{3}\)  + \(^{\dfrac{1}{3}}\) . \(\dfrac{7}{18}\) : \(\dfrac{7}{12}\)

 = \(\dfrac{2}{3}\) + \(\dfrac{7}{54}\) : \(\dfrac{7}{12}\)

 = \(\dfrac{2}{3}\) + \(\dfrac{2}{9}\)

 = \(\dfrac{8}{9}\)

Answer 3

2 /3 + 1/ 3 . ( − 4 9 + 5 6 ) : 7 /12

= 2/ 3 + 1 /3 . 7 /18 . 12/ 7

= 2/ 3 + 7 /48 . 12 /7

= 2/ 3 + 1/ 4

= 11/ 12

Answer 4

Ta có: \(\dfrac{2}{3}+\dfrac{1}{3}\left(\dfrac{-4}{9}+\dfrac{5}{6}\right):\dfrac{7}{12}\)

\(=\dfrac{2}{3}+\dfrac{1}{3}\cdot\dfrac{12}{7}\cdot\left(\dfrac{-8}{18}+\dfrac{15}{18}\right)\)

\(=\dfrac{2}{3}+\dfrac{4}{7}\cdot\dfrac{-7}{18}\)

\(=\dfrac{2}{3}-\dfrac{4}{18}\)

\(=\dfrac{2}{3}-\dfrac{2}{9}=\dfrac{6}{9}-\dfrac{2}{9}=\dfrac{4}{9}\)

Answer 5

\(\dfrac{2}{3}+\dfrac{1}{3}.\left(-\dfrac{4}{9}+\dfrac{5}{6}\right):\dfrac{7}{12}\) 

\(=\dfrac{2}{3}+\dfrac{1}{3}.\dfrac{7}{18}:\dfrac{7}{12}\) 

\(=\dfrac{2}{3}+\dfrac{2}{9}\) 

\(=\dfrac{8}{9}\)