$\text{1.}$ `27 6/13` `:` `(-5/7)` `-13 6/13` `:` `(-5/7)`
$\equiv$ `27 6/13` `.` `(-7/5)` `-13 6/13` `.` `(-7/5)`
$\equiv$ `(-7/5)` `.` `(27 6/13` `-` `13 6/13)`
$\equiv$ `(-7/5)` `.` `14`
$\equiv$ `-98/5`
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$\text{2.}$ `(2/25` `-` `1,008)` `:` `4/7` `:` `[(3 1/4-6 5/9).2 2/17]`
$\equiv$ `(0,08` `-` `1,008)` `.` `7/4` `:` `[(13/4-59/9).36/17]`
$\equiv$ `(-0,928)` `.` `7/4` `:` `[(117/36-236/36).36/17]`
$\equiv$ `-116/125` `.` `7/4` `:` $\text{[}$ `-119/36` $\text{.}$ `36/17` $\text{]}$
$\equiv$ `-116/125` `.` `7/4` `:` `-119/17`
$\equiv$ `-116/125` `.` `7/4` `.` `-17/119`
$\equiv$ `-116/125` `.` `-1/4`
$\equiv$ `29/125`
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$\text{3.}$ $2^3 + 3 . $ `(1/2)^0` $+$ $\text{(}$ $2^2$ $:$ `1/2` $\text{). 8}$
$\equiv$ $\text{8+3.1+(}$ $\text{4.2).8}$
$\equiv$ $\text{8+3+}$ $\text{8.8}$
$\equiv$ $\text{8+3+64}$
$\equiv$ $\text{11+64}$
$\equiv$ $\text{75}$
