Thực hiện phép tính: ​(frac{4}{5} – frac{7}{6} + frac{{ – 6}}{{15}})

Ta có:

(;begin{array}{*{20}{l}}
  begin{gathered}
  frac{4}{5} – frac{7}{6} + frac{{ – 6}}{{15}} hfill \
   = frac{{4.6}}{{5.6}} – frac{{5.7}}{{6.5}} + frac{{ – 6.2}}{{15.2}} hfill \
   = frac{{24}}{{30}} – frac{{35}}{{30}} + frac{{ – 12}}{{30}} hfill \ 
end{gathered}  \ 
  begin{gathered}
   = frac{{24 – 35 + ( – 12)}}{{30}} hfill \
   = frac{{ – 23}}{{30}} hfill \ 
end{gathered}  
end{array})