Đáp án:
$\begin{array}{l}
a)100:\left\{ {250:\left[ {350 - \left( {{{4.5}^3} - {2^3}.25} \right)} \right]} \right\}\\
= 100:\left\{ {250:\left[ {350 - \left( {4.125 - 8.25} \right)} \right]} \right\}\\
= 100:\left\{ {250:\left[ {350 - \left( {500 - 200} \right)} \right]} \right\}\\
= 100:\left\{ {250:\left[ {350 - 300} \right]} \right\}\\
= 100:\left( {250:50} \right)\\
= 100:5\\
= 20\\
b)703 - 140:\left( {38 + {2^5}} \right) - \frac{{{{17}^6}{{.17}^9}}}{{{{17}^{13}}}}\\
= 703 - 140:\left( {38 + 32} \right) - \frac{{{{17}^{15}}}}{{{{17}^{13}}}}\\
= 703 - 140:70 - {17^2}\\
= 702 - 2 - 289\\
= 700 - 289\\
= 411
\end{array}$
