bài 1 : tìm x, biết 

1) \(x+\frac{7}{12}=\frac{17}{18}-\frac{1}{9}\)                                                          2) \(\frac{29}{30}-\left(\frac{13}{23}+x\right)=\frac{7}{69}\)

bài 2 : tìm x thuộc Z , biết

1) \(\frac{-5}{6}.\frac{120}{25}< x< \frac{-7}{15}.\frac{9}{14}\)                                         2) \(\left(\frac{-5}{3}\right)^3< x< \frac{-24}{25}.\frac{-5}{6}\)

Tính giá trị biểu thức

\(1.A=\frac{1}{5}+\frac{3}{17}-\frac{4}{3}+\left(\frac{4}{5}-\frac{3}{17}+\frac{1}{3}\right)-\frac{1}{7}+\left[\frac{-14}{30}\right]\)

\(2.B=\left(\frac{5}{8}-\frac{4}{12}+\frac{3}{2}\right)-\left(\frac{5}{8}+\frac{9}{13}\right)-\left[\frac{-3}{2}\right]+\frac{7}{-15}\)

\(3.C=\frac{5}{18}+\frac{8}{19}-\frac{7}{21}+\left(\frac{-10}{36}+\frac{11}{19}+\frac{1}{3}\right)-\frac{5}{8}\)

\(4.D=\frac{1}{9}-\left[\frac{-5}{23}\right]-\left(\frac{-5}{23}+\frac{1}{9}+\frac{25}{7}\right)+\frac{50}{14}-\frac{7}{30}\)

\(5.E=\frac{1}{13}+\left(\frac{-5}{18}-\frac{1}{13}+\frac{12}{17}\right)+\left(\frac{12}{17}+\frac{5}{18}+\frac{7}{5}\right)\)

\(6.F=\frac{15}{14}-\left(\frac{17}{23}-\frac{80}{87}+\frac{5}{4}\right)+\left(\frac{12}{17}-\frac{15}{14}+\frac{1}{4}\right)\)

\(7.G=\frac{1}{25}-\frac{4}{27}+\left(\frac{-23}{27}+\frac{-1}{25}-\frac{5}{43}\right)+\frac{5}{43}-\frac{4}{7}\)

\(8.H=\frac{4}{15}-\frac{23}{28}-\left(\frac{-23}{28}+\frac{-11}{15}-\frac{29}{27}\right)-\frac{2}{27}\)

\(9.K=\frac{1}{16}-\frac{5}{21}+\left(\frac{-1}{16}+\frac{-3}{5}-\frac{-5}{21}\right)+\frac{-2}{5}+\frac{3}{4}\)

\(10.L=\frac{7}{12}+\frac{15}{14}-\left(\frac{14}{22}+\frac{-1}{14}+\frac{5}{21}\right)-\frac{-5}{21}+\frac{3}{5}\)

Tìm x , biết :

a) \(x+\frac{7}{12}=\frac{17}{18}-\frac{1}{9}\)  
b) \(\frac{29}{30}-\left(\frac{13}{23}+x\right)=\frac{7}{69}\)

c) \(\frac{-5}{6}.\frac{125}{25}< x< \frac{-7}{15}.\frac{9}{14}\)  (\(x\) thuộc Z)

d) \(\left(\frac{-5}{3}^3\right)< x< \frac{-24}{35}.\frac{-5}{6}\)  ( \(x\)  thuộc Z ) \(\)ththu

1) Tính hợp lý

a)\(\frac{31}{23}-\left(\frac{7}{32}+\frac{8}{32}\right)\)

b)\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)

c)\(\frac{38}{45}-\left(\frac{8}{45}-\frac{17}{51}-\frac{3}{11}\right)\)

d)\(\left(\frac{17}{28}+\frac{18}{29}-\frac{19}{30}-\frac{30}{31}\right).\left(-\frac{5}{12}+\frac{1}{4}+\frac{1}{6}\right)\)

Tính

\(1\frac{5}{7}-\frac{5}{7}.\frac{2}{11}-\frac{5}{7}.\frac{9}{11}\)

\(\frac{3}{11}.\frac{7}{19}.\frac{17}{11}.\frac{3}{9}-\frac{3}{19}.\frac{15}{11}\)

\(\frac{5}{11}.\frac{18}{29}-\frac{5}{11}.\frac{8}{29}+\frac{5}{11}.\frac{19}{26}\)

\(\frac{17}{23}.\frac{8}{16}.\frac{27}{17}.80.\frac{3}{4}\)

\(\left(\frac{13}{23}+\frac{1313}{2323}-\frac{131313}{232323}\right).\left(\frac{1}{3}+\frac{1}{4}-\frac{7}{12}\right)\)

Timf x,y

1) x+\(\frac{7}{12}\)=\(\frac{17}{18}\)-\(\frac{1}{9}\)

2)\(\frac{29}{30}\)-(\(\frac{13}{23}\)+x)=\(\frac{7}{69}\)

3)\(\frac{x}{15}=\frac{4}{10}\)

4)\(\frac{x-3}{49}=\frac{-2}{7}\)

5)\(\frac{x}{3}=\frac{1}{y}\)