Question

Tính

a) \(\left(-\frac{2}{3}+\frac{3}{7}\right):\frac{4}{5}+\left(-\frac{1}{3}+\frac{4}{7}\right):\frac{4}{5}\)

b) \(\frac{5}{9}:\left(\frac{1}{11}-\frac{5}{22}\right)+\frac{5}{9}:\left(\frac{1}{15}-\frac{2}{3}\right)\)

Answer 1

\(\left(\frac{-2}{3}+\frac{3}{7}\right):\frac{4}{5}+\left(\frac{-1}{3}+\frac{4}{7}\right):\frac{4}{5}\)

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

\(=\left[\left(\frac{-2}{3}+\frac{-1}{3}\right)+\left(\frac{3}{7}+\frac{4}{7}\right)\right]:\frac{4}{5}\)

\(=\left[\left(-1+1\right)\right]:\frac{4}{5}\)

\(=0:\frac{4}{5}=0\)

~ Hok tốt ~

Answer 2

cau A= o nha ban con cau B minh ko chac vi so minh ra hoi lon 1 ti

Answer 3

a,\(\left(-\frac{2}{3}+\frac{3}{7}\right):\frac{4}{5}+\left(-\frac{1}{3}+\frac{4}{7}\right):\frac{4}{5}\)

=\(\left[\left(-\frac{2}{3}+\frac{3}{7}\right)+\left(-\frac{1}{3}+\frac{4}{7.}\right)\right]:\frac{4}{5}\)

=\(\left[-\frac{5}{21}+\frac{5}{21}\right]:\frac{4}{5}\)

=\(0:\frac{4}{5}=0\)

b,\(\frac{5}{9}:\left(\frac{1}{11}-\frac{5}{22}\right)+\frac{5}{9}:\left(\frac{1}{15}-\frac{2}{3}\right)\)

=\(\frac{5}{9}:\left[\left(\frac{1}{11}-\frac{5}{22}\right)+\left(\frac{1}{15}-\frac{2}{3}\right)\right]\)

=\(\frac{5}{9}:\left[-\frac{3}{22}-\frac{3}{5}\right]\)

=\(\frac{5}{9}:\left[-\frac{81}{110}\right]\)

=\(-\frac{550}{729}\)

#hok tốt#