Tính giá trị các biểu thức sau bằng cách hợp lý nhất: a) (-25) + 58 - 375 b) 781 – 332 + 129 – 68 c) 56 - 141 - (-244) – 359 d) 32 - [97 - (132 + 297)]

a) $\displaystyle ( -25) \ +\ 58\ -\ 375$
$\displaystyle  \begin{array}{{>{\displaystyle}l}}
=\ ( -25) \ +\ 58\ -\ 375\\
=\ ( -25) \ -\ 375\ +\ 58\\
=\ -400\ +\ 58\\
=\ -342
\end{array}$

b) $\displaystyle 781\ –\ 332\ +\ 129\ –\ 68$
$\displaystyle  \begin{array}{{>{\displaystyle}l}}
=\ ( 781\ +\ 129) \ -\ ( 332\ +\ 68)\\
=\ 910\ -\ 400\\
=\ 510
\end{array}$

c) $\displaystyle 56\ -\ 141\ -\ ( -244) \ –\ 359$
$\displaystyle  \begin{array}{{>{\displaystyle}l}}
=\ 56\ -\ 141\ +\ 244\ -\ 359\\
=\ ( 56\ +\ 244) \ -\ ( 141\ +\ 359)\\
=\ 300\ -\ 500\\
=\ -200
\end{array}$

d)$\displaystyle \ 32\ -\ [ 97\ -\ ( 132\ +\ 297)]$
$\displaystyle  \begin{array}{{>{\displaystyle}l}}
=\ 32\ -\ ( 97\ -\ 429)\\
=\ 32\ -\ ( -332)\\
=\ 32\ +\ 332\\
=\ 364
\end{array}$