$75.(-\dfrac{4}{25}-7\dfrac{1}{5}+4\dfrac{7}{45})$
$=75.(-\dfrac{4}{25})-75.(7\dfrac{1}{5})+75.(4\dfrac{7}{45})$
$=-12-75-75.\dfrac{36}{5}+75.\dfrac{187}{45}$
$=-12-540+\dfrac{935}{3}$
$=-552+\dfrac{935}{3}$
$=-\dfrac{1656}{3}+\dfrac{935}{3}$
$=-\dfrac{721}{3}$