\(\dfrac{-1}{7}-\dfrac{1}{8}\)

\(\dfrac{-15}{48}-\dfrac{1}{12}\)

\(\dfrac{-3}{4}-\dfrac{4}{5}\)

\(\dfrac{3}{4}+\dfrac{-5}{6}-\dfrac{11}{12}\)

\(\dfrac{-7}{9}+\dfrac{-2}{9}\)

\(\dfrac{15}{4}-\dfrac{-3}{4}\)

\(\dfrac{1}{6}-\dfrac{1}{36}\)

\(1-\dfrac{3}{2}\)

\(2-\dfrac{4}{5}\)

\(\dfrac{-1}{8}+\dfrac{-5}{8}\)

\(\dfrac{-3}{7}+\dfrac{5}{7}\)

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

\(\dfrac{-2}{3}+\dfrac{1}{5}\)

\(\dfrac{-2}{13}+\dfrac{-5}{26}\)

\(\dfrac{-4}{7}+\dfrac{1}{3}\)

tính nhanh :

\(\dfrac{-1}{6}+\dfrac{5}{-12}+\dfrac{7}{12}\)

\(\dfrac{4}{45}+\dfrac{-1}{45}+\dfrac{7}{45}+\dfrac{4}{45}+\dfrac{-2}{45}+\dfrac{-1}{5}\)