e) \(E=0,7.2\frac{2}{3}.20.0,375.\frac{5}{28}\)

        \(=\left(0,7.20\right)\left(2\frac{2}{3}.0,375\right)\frac{5}{28}\)

        \(=14.1.\frac{5}{28}\)

        \(=14.\frac{5}{28}\)

        \(=\frac{5}{2}\)

f) \(F=\left(9,75.21\frac{3}{7}+\frac{39}{4}.18\frac{4}{7}\right)\frac{15}{78}\)

       \(=\left(\frac{39}{4}.21\frac{3}{7}+\frac{39}{4}.18\frac{4}{7}\right)\frac{15}{78}\)

       \(=\frac{39}{4}\left(21\frac{3}{7}+18\frac{4}{7}\right)\frac{15}{78}\)

       \(=\frac{39}{4}.40.\frac{15}{78}\)

       \(=390.\frac{15}{78}\)

       \(=78\)

Chúc bạn học tốt môn Toán!!!

Mình ko ghi đề đâu

\(A=49\frac{8}{23}-5\frac{7}{32}-14\frac{8}{23}=\left(49\frac{8}{23}-14\frac{8}{23}\right)-5\frac{7}{32}=35-5\frac{7}{32}=29\frac{25}{32}\)

\(B=71\frac{38}{45}-43\frac{8}{45}+1\frac{17}{57}=\left(71\frac{38}{45}-43\frac{8}{45}\right)+1\frac{17}{57}=28\frac{2}{3}+1\frac{17}{57}=29\frac{55}{57}\)

\(C=-\frac{3}{7}.\left(\frac{5}{9}+\frac{4}{9}\right)+2\frac{3}{7}=-\frac{3}{7}.1+2\frac{3}{7}=-\frac{3}{7}+2\frac{3}{7}=2\)

a) \(A=49\frac{8}{23}-\left(5\frac{7}{32}+14\frac{8}{23}\right)\)

        \(=\left(49\frac{8}{23}-14\frac{8}{23}\right)-5\frac{7}{32}\)

        \(=35-5\frac{7}{32}\) 

        \(=34\frac{32}{32}-5\frac{7}{32}\)       

        \(=29\frac{25}{32}\) 

b) \(B=71\frac{38}{45}-\left(43\frac{8}{45}-1\frac{17}{57}\right)\)

        \(=\left(71\frac{38}{45}-43\frac{8}{45}\right)+1\frac{17}{57}\)

        \(=28\frac{2}{3}+1\frac{17}{57}\)  

        \(=28\frac{38}{57}+1\frac{17}{57}\)

        \(=29\frac{55}{57}\)

c) \(C=\frac{-3}{7}.\frac{5}{9}+\frac{4}{9}.\frac{-3}{7}+2\frac{3}{7}\)

        \(=\frac{-3}{7}\left(\frac{5}{9}+\frac{4}{9}\right)+2\frac{3}{7}\)

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

        \(=2\)

d) \(D=\left(19\frac{5}{8}:\frac{7}{12}-13\frac{1}{4}:\frac{7}{12}\right)\frac{4}{5}\)

        \(=\left(19\frac{5}{8}-13\frac{1}{4}\right):\frac{7}{12}.\frac{4}{5}\)

        \(=\frac{51}{8}:\frac{7}{12}.\frac{4}{5}\)

        \(=\frac{153}{14}.\frac{4}{5}\)

        \(=\frac{306}{35}\)

  \(=49\frac{8}{23}-5\frac{7}{32}-14\frac{8}{23}\)

\(=\left(49\frac{8}{23}-14\frac{8}{23}\right)-5\frac{7}{32}\)

\(=35\frac{0}{23}-5\frac{7}{32}\)

\(=\frac{805}{23}-\frac{167}{32}\)

\(\frac{25760}{736}-\frac{3841}{736}\)

\(=\frac{21919}{736}=\frac{953}{32}\)

1135/23-167/32+330/23

=(1135/23-330/23)+167/32

=805/23+167/32

=35+167/32

=1120/32+167/32

=1287/32

A= \(49\frac{8}{23}-\left(5\frac{7}{32}+14\frac{8}{23}\right)\)

=\(\frac{1135}{32}-\left(\frac{167}{32}+\frac{330}{23}\right)\)

=\(\frac{1135}{23}-\frac{167}{32}-\frac{330}{23}\)

=\(\left(\frac{1135}{23}-\frac{330}{23}\right)-\frac{167}{32}\)

=\(\frac{805}{23}-\frac{167}{32}\)

=\(\frac{953}{32}\)

B=\(6\frac{3}{8}+5\frac{1}{2}\)

=\(\frac{51}{8}+\frac{11}{2}\)

=\(\frac{51}{8}+\frac{44}{8}\)

=\(\frac{51+44}{8}\)

=\(\frac{95}{8}\)

a,\(\frac{21}{25}.\frac{11}{9}.\frac{5}{7}=\frac{21.11.5}{25.9.7}=\frac{3.7.11.5}{5^2.3^2.7}=\frac{11}{5.3}=\frac{11}{15}\)

b,\(\frac{5}{23}.\frac{17}{26}+\frac{5}{23}.\frac{9}{26}=\frac{5}{23}.\left(\frac{17}{26}+\frac{9}{26}\right)=\frac{5}{23}.1=\frac{5}{23}\)

c, \(\left(\frac{3}{29}-\frac{1}{5}\right).\frac{29}{3}=\frac{3}{29}.\frac{29}{3}-\frac{1}{5}.\frac{29}{3}=1-\frac{29}{15}=-\frac{14}{15}\)

a , \(\frac{21}{25}\times\frac{11}{9}\times\frac{5}{7}\) 

\(=\frac{21\times11\times5}{25\times9\times7}\)

\(=\frac{3\times7\times11\times5}{5\times5\times3\times3\times7}\) 

\(=\frac{11}{5\times3}\) 

\(=\frac{11}{15}\) 

b ,   \(\frac{5}{23}\times\frac{17}{26}+\frac{5}{23}\times\frac{9}{26}\) 

\(=\frac{5}{23}\times\left(\frac{17}{26}+\frac{9}{26}\right)\)

\(=\frac{5}{23}\times\frac{26}{26}\) 

\(=\frac{5}{23}\times1\) 

\(=\frac{5}{23}\) 

c , \(\left(\frac{3}{29}-\frac{1}{5}\right)\times\frac{29}{3}\) 

\(=\frac{3}{29}\times\frac{29}{3}-\frac{1}{5}\times\frac{29}{3}\) 

\(=1-\frac{29}{15}\) 

c=39/64

d=913/105

3) C thiếu đề

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

\(D=\frac{1}{9}-\frac{5}{23}+\frac{5}{23}-\frac{1}{9}-\frac{25}{7}+\frac{50}{4}-\frac{7}{30}\)

\(D=\frac{1}{9}-\frac{1}{9}-\frac{5}{23}+\frac{5}{23}+\frac{-25}{7}+\frac{50}{4}-\frac{7}{30}\)

\(D=0+0+\frac{125}{14}-\frac{7}{30}\)

\(D=\frac{913}{105}\)

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

\(C=\frac{5}{18}+\frac{8}{19}-\frac{1}{3}+\frac{-5}{18}+\frac{11}{19}+\frac{1}{3}-\frac{5}{8}\)

\(C=\left(\frac{5}{18}+\frac{-5}{18}\right)+\left(\frac{8}{19}+\frac{11}{19}\right)+\left(\frac{-1}{3}+\frac{1}{3}\right)-\frac{5}{8}\)

\(C=0+1+0-\frac{5}{8}\)

\(C=\frac{3}{8}\)