Thực hiện phép tính (Hộp lí nếu có thể) (a) 327 + [ ( − 83 ) + ( − 327 ) + 73 ] . (b) 4. ( − 25 ) .8 . ( − 9 ) .

a) \(327 + \left[ {\left( { - 83} \right) + \left( { - 327} \right) + 73} \right]\)

\( = 327 + \left( { - 83} \right) + \left( { - 327} \right) + 73\)

\( = \left[ {327 + \left( { - 327} \right)} \right] + \left[ {\left( { - 83} \right) + 73} \right]\)

\( = 0 + \left( { - 10} \right)\)\( = - 10\).

b) \(4.\left( { - 25} \right).8.\left( { - 9} \right)\)

\( = \left( { - 100} \right).\left( { - 72} \right)\)

\( = 7200\).

c) \(29.\left( { - 13} \right) + 27.\left( { - 29} \right)\)

\[ = 29.\left( { - 13} \right) + \left( { - 27} \right).29\]

\[ = 29.\left[ {\left( { - 13} \right) + \left( { - 27} \right)} \right]\]

\[ = 29.\left( { - 40} \right)\]\[ = - 1160\].

d) \({\left( { - 18} \right)^2} - \left\{ {159 - 2.\left[ {{7^2} + \left( {94 - 127} \right):\left( {6 - {3^2}} \right)} \right]} \right\}\)

\( = {\left( { - 18} \right)^2} - \left\{ {159 - 2.\left[ {49 + \left( { - 33} \right):\left( {6 - 9} \right)} \right]} \right\}\)

\( = 324 - \left\{ {159 - 2.\left[ {49 + \left( { - 33} \right):\left( { - 3} \right)} \right]} \right\}\)

\( = 324 - \left\{ {159 - 2.\left[ {49 + 11} \right]} \right\}\)

\( = 324 - \left\{ {159 - 2.60} \right\}\)

\( = 324 - 39 = 285\).