\(\left(\frac{1}{4}-\frac{2}{5}\right):\frac{23}{25}+\left(\frac{3}{4}-\frac{3}{5}\right):\frac{23}{25}\)
\(=\left(\frac{1}{4}-\frac{2}{5}+\frac{3}{4}-\frac{3}{5}\right).\frac{25}{23}\)
\(=-\frac{25}{23}\)
\(\left(\frac{1}{4}+\frac{-2}{5}\right):\frac{23}{25}+\left(\frac{3}{4}+\frac{-3}{5}\right):\)\(\frac{23}{25}=\)\(\left[\left(\frac{1}{4}+\frac{-2}{5}\right)+\left(\frac{3}{4}+\frac{-3}{5}\right)\right]:\)\(\frac{23}{25}\)
\(=\) \(\left[\frac{1}{4}+\frac{-2}{5}+\frac{3}{4}+\frac{-3}{5}\right]:\frac{23}{25}\)
\(=\left[\left(\frac{1}{4}+\frac{3}{4}\right)+\left(\frac{-2}{5}+\frac{-3}{5}\right)\right]:\frac{23}{25}\)
\(=\left[\frac{4}{4}+\frac{-5}{5}\right]:\frac{23}{25}=\left[1+\left(-1\right)\right]:\frac{23}{25}\)
\(=0:\frac{23}{25}=0.\frac{25}{23}=\frac{0}{23}=0\)