Question

Tính :

a) \(\dfrac{-2}{5}+25\%\) b) \(\dfrac{-2}{3}.\dfrac{8}{11}+\dfrac{-2}{3}.\dfrac{3}{11}\) c) \(\dfrac{-3}{4}.\dfrac{7}{8}+1\dfrac{1}{2}+\dfrac{-3}{4}:\dfrac{8}{9}\)

Answer 1

\(\dfrac{-2}{5}+25\%=\dfrac{-2}{5}+\dfrac{1}{4}=\dfrac{-3}{20}\)

\(\dfrac{-2}{3}.\dfrac{8}{11}+\dfrac{-2}{3}.\dfrac{3}{11}=\dfrac{-2}{3}\left(\dfrac{8}{11}+\dfrac{3}{11}\right)=\dfrac{-2}{3}.1=\dfrac{-2}{3}\)

\(\dfrac{-3}{4}.\dfrac{7}{8}+1\dfrac{1}{2}+\dfrac{-3}{4}:\dfrac{8}{9}=\dfrac{-3}{4}.\dfrac{7}{8}+\dfrac{-3}{4}.\dfrac{9}{8}+\dfrac{3}{2}=\dfrac{-3}{4}.2+\dfrac{3}{2}=\dfrac{-3}{2}+\dfrac{3}{2}=0\)