Đáp án:

$\begin{array}{l}
a)\frac{{3x - 2}}{2} = \frac{{2x + 1}}{3}\\
 \Rightarrow 3\left( {3x - 2} \right) = 2\left( {2x + 1} \right)\\
 \Rightarrow 9x - 6 = 4x + 2\\
 \Rightarrow 9x - 4x = 2 + 6\\
 \Rightarrow 5x = 8\\
 \Rightarrow x = \frac{8}{5}\\
b)\frac{{5\left( {x - 1} \right) + 2}}{6} - \frac{{7x - 1}}{4} = \frac{{2\left( {2x + 1} \right) - 5}}{7}\\
 \Rightarrow \frac{{5x - 3}}{6} - \frac{{7x - 1}}{4} = \frac{{4x - 3}}{7}\\
 \Rightarrow \frac{{14\left( {5x - 3} \right) - 21\left( {7x - 1} \right)}}{{84}} = \frac{{12\left( {4x - 3} \right)}}{{84}}\\
 \Rightarrow 70x - 42 - 84x + 21 = 48x - 36\\
 \Rightarrow 48x + 84x - 70x =  - 42 + 21 + 36\\
 \Rightarrow 62x = 15\\
 \Rightarrow x = \frac{{15}}{{62}}\\
c)\frac{{2\left( {3x + 1} \right) + 1}}{4} - 5 = \frac{{2\left( {3x - 1} \right)}}{5} - \frac{{3x + 2}}{{10}}\\
 \Rightarrow \frac{{5\left( {6x + 3} \right) - 5.20}}{{20}} = \frac{{4\left( {6x - 2} \right) - 2\left( {3x + 2} \right)}}{{20}}\\
 \Rightarrow 30x + 15 - 100 = 24x - 8 - 6x - 4\\
 \Rightarrow 30x - 24x + 6x = 100 - 15 - 8 - 4\\
 \Rightarrow 12x = 73\\
 \Rightarrow x = \frac{{73}}{{12}}
\end{array}$