\[\boxed{\text{164\ (164).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[x^{2} - x^{3} = {0,1}^{2} - {0,1}^{3} =\]
\[= 0,01 - 0,001 = 0,009.\]
\[15a^{2} = 15 \cdot {0,4}^{2} = 15 \cdot 0,16 =\]
\[= 2,4.\]
\[(x - y)^{5} = (0,8 - 0,6)^{5} =\]
\[= {0,2}^{5} = 0,00032.\]
\[a^{2}b^{3} = {0,6}^{2} \cdot {0,5}^{3} =\]
\[= 0,36 \cdot 0,125 = 0,045\text{.\ }\]
\[\left( x^{2} - y^{2} \right)\ :(x - y) =\]
\[= \frac{(x - y) \cdot (x + y)}{x - y} = x + y =\]
\[= 5 + 3 = 8.\]
\[\left( x^{2} - y^{2} \right)\ :x - y =\]
\[= \left( 5^{2} - 3^{3} \right)\ :5 - 3 =\]
\[= (25 - 9)\ :5 - 3 =\]
\[= 16\ :5 - 3 = 3,2 - 3 = 0,2.\]
\[x^{2} - y^{2}\ :(x - y) =\]
\[= 25 - 9\ :(5 - 3) =\]
\[= 25 - 9\ :2 = 25 - 4,5 =\]
\[= 20,5.\]
\[x^{2} - y^{2}\ :x - y =\]
\[= 25 - 9\ :5 - 3 =\]
\[= 25 - 1,8 - 3 = 20,2.\]