\[\mathbf{Страница\ 27.}\]
\[\boxed{\mathbf{7.}}\]
\[8 = 2 + 6 = 5 + 3 = 4 + 4\]
\[Ответ:3\ способа.\]
\[\boxed{\mathbf{8.}}\]
\[5 \cdot 4\ :2 = 10\ (способов).\]
\[Ответ:10\ способов.\]
\[\boxed{\mathbf{9.}}\]
\[6 \cdot 5 \cdot 4 \cdot 3 \cdot 2 = 720\ способов.\]
\[Ответ:\ 720\ способов.\]
\[\boxed{\mathbf{10.}}\]
\[И\] | \[Т\] | \[О\] | \[З\] | \[М\] | |
---|---|---|---|---|---|
\[И\] | \[-\] | \[ИТ\] | \[ИО\] | \[ИЗ\] | \[ИМ\] |
\[Т\] | \[ИТ\] | \[-\] | \[ТО\] | \[ТЗ\] | \[ТМ\] |
\[О\] | \[ОИ\] | \[ОТ\] | \[-\] | \[ОЗ\] | \[ОМ\] |
\[З\] | \[ЗИ\] | \[ЗТ\] | \[ЗО\] | \[-\] | \[ЗМ\] |
\[М\] | \[МИ\] | \[МТ\] | \[МО\] | \[МЗ\] | \[-\] |
\[Ответ:10\ способов.\]
\[\boxed{\mathbf{11.}}\]
\[\textbf{а)}\ 4 \cdot 4 \cdot 4 = 64\ (способа).\]
\[\textbf{б)}\ 3 \cdot 4 \cdot 4 = 48\ (способов).\]
\[\boxed{\mathbf{12.}}\]
\[\textbf{а)}\ 5 \cdot 5 \cdot 5 = 125\ чисел.\]
\[\textbf{б)}\ 5 \cdot 4 \cdot 3 = 60\ чисел.\]