\[\boxed{\mathbf{6.94}}\]
\[\textbf{а)}\ 9 - 60 = - 51 - 11 =\]
\[= - 62\ :2 = - 31 \cdot ( - 3) = 93\]
\[\textbf{б)} - 22 + 100 = 78\ :( - 6) =\]
\[= - 13 - 18 = - 31 + 5 = - 26\]
\[\textbf{в)} - 21 - 54 = - 75\ :15 =\]
\[= - 5 - 9 = - 14\ :( - 11) =\]
\[= \frac{14}{11} = 1\frac{3}{11}\]
\[\textbf{г)} - 15 \cdot 70 = - 1050\ :7 =\]
\[= - 150 \cdot ( - 2) = 300 - 150 =\]
\[= 150\]