\[\boxed{\mathbf{10}\mathbf{.}}\]
\[\textbf{б)}\ 54 - 7 + 10 = 47 + 10 = 57\]
\[61 + 20 - 6 = 81 - 6 = 75\]
\[87 - 50 - 8 = 37 - 8 = 29\]
\[36 - (9 + 0) = 36 - 9 = 27\]
\[53 - (7 - 0) = 53 - 7 = 46\]
\[92 + 0 - 3 = 92 - 3 = 89\]