a) \(\left(6-\frac{2}{3}+\frac{1}{2}\right)-\left(5+\frac{5}{3}-\frac{3}{2}\right)-\left(3-\frac{7}{3}+\frac{5}{2}\right)\)

\(=6-\frac{2}{3}+\frac{1}{2}-5-\frac{5}{3}+\frac{3}{2}-3+\frac{7}{3}-\frac{5}{2}\)

\(=\left(-\frac{2}{3}-\frac{5}{3}+\frac{7}{3}\right)+\left(\frac{1}{2}+\frac{3}{2}-\frac{5}{2}\right)+\left(6-5-3\right)\)

\(=0+2-\frac{5}{2}+\left(-2\right)=\left(2-2\right)-\frac{5}{2}=0-\frac{5}{2}=-\frac{5}{2}\)

\(\left(3-\frac{1}{4}+\frac{2}{3}\right)-\left(5-\frac{1}{3}-\frac{6}{5}\right)-\left(6-\frac{7}{4}+\frac{3}{2}\right)\)

\(=3-\frac{1}{4}+\frac{2}{3}-5+\frac{1}{3}+\frac{6}{5}-6+\frac{7}{4}-\frac{3}{2}\)

\(=\left(3-5-6\right)+\left(\frac{-1}{4}+\frac{7}{4}\right)+\left(\frac{2}{3}+\frac{1}{3}\right)+\left(\frac{6}{5}-\frac{3}{2}\right)\)

\(=\left(-8\right)+2+1+\frac{-3}{10}\)

\(=\left(-5\right)+\frac{-3}{10}=\frac{-53}{10}=-5,3\)

(3-1/4+2/3)-(5-1/3-6/5)-(6-7/4+3/2)

=3-1/4+2/3-5-1/3-6/5-6-7/4+3/2

=(3-5-6)+(-1/4-7/4)+(2/3-1/3)+(6/5/3/2

=(-8)+2+1+(-3/10)

=(-5)+(-3/10)=-53/10=-5,3

-5,8 chứ???

\(-\dfrac{2}{5}.\dfrac{4}{7}+\dfrac{-3}{5}.\dfrac{2}{7}+\dfrac{-3}{5}\)

= \(\dfrac{-8}{35}+\dfrac{-6}{35}+\dfrac{-3}{5}\) 

=\(\dfrac{-8-6-21}{35}\) 

=\(\dfrac{-35}{35}\) 

=-1

`(-2)/5.4/7+(-3)/5.2/7+(-3)/5`

`=(-8)/3 +(-6)/35+(-3)/5`

`=(-8)-6-21/35`

`=(-35)/35`

`=(-1)`

`@Nae`

(-2)/5 x 4/7 + (-3)/5 x 2/7 + (-3)/5

`=(-8)/3 +(-6)/35+(-3)/5`

`=(-8)-6-21/35`

`=(-35)/35`

`=(-1)`

`@Nae`

a) \(\dfrac{\dfrac{3}{14}-\dfrac{3}{17}+\dfrac{3}{19}}{\dfrac{5}{19}+\dfrac{5}{14}-\dfrac{5}{17}}=\dfrac{3\left(\dfrac{1}{14}-\dfrac{1}{17}+\dfrac{1}{19}\right)}{5\left(\dfrac{1}{14}-\dfrac{1}{17}+\dfrac{1}{19}\right)}=\dfrac{3}{5}\)

c) \(\dfrac{\dfrac{2}{7}+\dfrac{2}{5}+\dfrac{2}{17}-\dfrac{2}{193}}{\dfrac{3}{7}+\dfrac{3}{5}+\dfrac{3}{17}-\dfrac{3}{293}}=\dfrac{2\left(\dfrac{1}{7}+\dfrac{1}{5}+\dfrac{1}{17}-\dfrac{1}{193}\right)}{3\left(\dfrac{1}{7}+\dfrac{1}{5}+\dfrac{1}{17}-\dfrac{1}{193}\right)}=\dfrac{2}{3}\)

d) 

Mk ko ghi lại đề nhé

1 = \(350-4.19+4.7\)

\(=350-4.\left(19+7\right)\)

\(=350+4.26\)

\(=350-104=246\)

2 Câu này mình vẫn chưa hiểu là bạn ghi 27  3/5 tức là 27.3/5 hay 27\(\dfrac{3}{5}\)nên mk bỏ qua nhé

3 Cái đoạn 1 1/3 y chang câu 2 

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

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

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

5 \(=2^2+10^2-\left[9.\left(112:8\right)-11\right].1\)

\(=4+100-\left(9.14-11\right)\)

\(=104-115\)\(=-11\)

6 Đoạn 6 3/5 y chang 2,3

7 \(=\left(\dfrac{2}{3}-1\right)+\left(\dfrac{2}{7}-\dfrac{3}{7}\right)-\left(\dfrac{1}{14}-\dfrac{3}{28}\right)\)

\(=\dfrac{-1}{3}+\dfrac{-1}{7}-\dfrac{-1}{28}\)

\(=\dfrac{-196}{588}+\dfrac{-84}{588}-\dfrac{-21}{588}\)\(=\dfrac{259}{588}\)

Làm tạm tạm thôi xl vì có 3 câu ko hiểu 

\(\left(\dfrac{1}{3}-\dfrac{3}{10}\right):\dfrac{3}{5}+\left(\dfrac{2}{3}-\dfrac{7}{10}\right):\dfrac{3}{5}\)
\(=\left(\dfrac{1.10}{3.10}-\dfrac{3.3}{10.3}\right).\dfrac{5}{3}+\left(\dfrac{2.10}{3.10}-\dfrac{7.3}{10.3}\right).\dfrac{5}{3}\)

\(=\left(\dfrac{10}{30}-\dfrac{9}{30}\right).\dfrac{5}{3}+\left(\dfrac{20}{30}-\dfrac{21}{30}\right).\dfrac{5}{3}\)

\(=\dfrac{1}{30}.\dfrac{5}{3}-\dfrac{1}{30}.\dfrac{5}{3}\)

\(=\dfrac{5}{3}.\left(\dfrac{1}{30}-\dfrac{1}{30}\right)\)

\(=\dfrac{5}{3}.0\)

\(=0\)

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