19: \(\left(0,75+\frac12\right):\left(-\frac12\right)^3-\left(1\frac25+3\frac12\right)^0\)
\(=\left(\frac34+\frac12\right):\frac{-1}{8}-1\)
\(=\left(\frac68+\frac48\right)\cdot\left(-8\right)-1=-10-1=-11\)
18: \(\left(\frac12+0,8-1\frac13\right)\cdot\left(2,3+4\frac{7}{25}-1,28\right)\)
\(=\left(\frac12+\frac45-\frac43\right)\left(2,3+4,28-1,28\right)\)
\(=\left(\frac{15}{30}+\frac{24}{30}-\frac{40}{30}\right)\left(2,3+3\right)=5,3\cdot\frac{-1}{30}=-\frac{5.3}{30}=-\frac{53}{300}\)
17: \(\left(3\frac14-6\frac54\right):\frac57+\frac13-\left(-\frac16\right):\left(-2\right)\)
\(=\left(3+\frac14-6-\frac54\right):\frac57+\frac13-\frac16:2\)
\(=\left(-3-1\right)\cdot\frac75+\frac13-\frac{1}{12}=-4\cdot\frac75+\frac{4}{12}-\frac{1}{12}=-\frac{28}{5}+\frac{3}{12}\)
\(=-\frac{28}{5}+\frac14=\frac{-112+5}{20}=\frac{-107}{20}\)
14: \(25\cdot\left(-\frac15\right)^3+\frac15-2\cdot\left(-\frac12\right)^2-\frac12\)
\(=25\cdot\frac{-1}{125}+\frac15-2\cdot\frac14-\frac12\)
\(=-\frac15+\frac15-\frac12-\frac12=-1\)
13: \(35\frac16:\left(-\frac45\right)-45\frac16:\left(-\frac45\right)\)
\(=\left(35+\frac16-45-\frac16\right):\left(-\frac45\right)\)
\(=-10\cdot\frac{-5}{4}=\frac{50}{4}=\frac{25}{2}\)
12: \(5\frac{5}{27}+\frac{7}{23}+0,5-\frac{5}{27}+\frac{16}{23}\)
\(=5+\frac{5}{27}-\frac{5}{27}+\frac{7}{23}+\frac{16}{23}+0,5\)
=5+1+0,5
=6,5
9: \(-3,75\cdot\left(-7,2\right)+2,8\cdot3,75\)
\(=3,75\cdot7,2+2,8\cdot3,75\)
\(=3,75\left(2,8+7,2\right)=3,75\cdot10=37,5\)
4: \(\frac{4^2\cdot4^3}{2^{10}}\cdot2004=\frac{4^5}{2^{10}}\cdot2004=2004\)
2: \(\left(1,25-\frac35\right):1\frac15+0,5\)
\(=\left(1,25-0,6\right):\frac65+0,5\)
\(=0,65\cdot\frac56+0,5=\frac{13}{20}\cdot\frac56+0,5=\frac{13}{24}+\frac{12}{24}=\frac{25}{24}\)
