\ANG{Berechne:\qquad
$\D\left(\frac{2}{3}\right)^{3}\cdot 5\frac{1}{4}
  -\frac{2}{3}\cdot\left(1\frac{2}{5}\right)^{2}+\frac{1}{\D\frac{15^{2}}{13^{2}}}$

}
\LSG{
$\D\frac{8\cdot 21}{27\cdot 4}-\frac{2}{3}\cdot\left(\frac{7}{5}\right)^{2}+
  \frac{169}{225}=
  \frac{14}{9}-\frac{98}{3\cdot 25}+\frac{169}{225}=$\\

$\D =\frac{14\cdot 25+98\cdot 3+169}{225}=\frac{350-294+169}{225}=\frac{225}{225}=1$\\
}
