tính bằng cách thuận tiện nhất 

a,\(\frac{6}{7}\cdot\frac{16}{15}\cdot\frac{7}{6}\cdot\frac{21}{32}\)b, \(\frac{21}{17}\cdot\frac{13}{14}\cdot56\cdot\frac{3}{42}\)  c,\(\frac{7}{4}\cdot\frac{11}{21}+\frac{11}{21}\cdot\frac{5}{4}\)   d,\(\frac{23}{14}\cdot\frac{6}{14}-\frac{9}{14}\cdot\frac{6}{13}\)

bài 1 : tính phân số:

a) \(\frac{5}{7}+\frac{4}{9}=?;\frac{4}{5}-\frac{2}{3}=?;\frac{9}{11}+\frac{3}{8}=?;\frac{16}{25}-\frac{2}{5}=?\)=?

b)\(5+\frac{3}{5}=?;10-\frac{9}{16}=?;\frac{2}{3}-\left(\frac{1}{6}+\frac{1}{8}\right)=?\)

c)\(\frac{5}{7}+\frac{7}{6}=?;\frac{7}{12}+\frac{17}{18}=?;\frac{9}{8}+\frac{15}{32}=?;4+\frac{35}{45}=?\)

d)\(\frac{11}{4}-\frac{15}{16}=?;\frac{5}{6}-\frac{5}{8}=?;\frac{196}{64}-2=?;3-\frac{13}{9}=?\)

e)\(\frac{8}{5}+\frac{7}{6}+\frac{5}{9}-2=?;3-\frac{5}{6}-\frac{4}{9}+\frac{32}{24}=?\)

​​​​\(\frac{9}{16}\)+\(\frac{37}{32}\);  \(\frac{126}{48}\)- \(\frac{12}{16}\) ;    \(\frac{19}{15}\)* \(\frac{32}{8}\) ;    \(\frac{23}{17}\): \(\frac{7}{24}\)

làm giúp mình nha bốn câu này nha

Tính

\(\frac{2}{5}+\frac{3}{10}-\frac{1}{2}= \)                                         

\(\frac{8}{11}+\frac{8}{33}\cdot\frac{3}{4}=\)                              \(\frac{5}{12}-\frac{7}{32}:\frac{21}{16}\)

\(\frac{7}{9}\cdot\frac{3}{4}:\frac{5}{8}=\) Giải giúp mink nhé!