Đáp án:
$\begin{array}{l}
a)A = 35.53 - 18\\
= 53.\left( {34 + 1} \right) - 18\\
= 53.34 + 53 - 18\\
= 53.34 + 35\\
\Rightarrow A = B\\
b)M = 137.454 + 200\\
= \left( {138 - 1} \right).454 + 200\\
= 138.454 - 454 + 200\\
= 138.454 - 254 < 138.454 - 110\\
\Rightarrow M < N\\
c)E = 1998.1998\\
= \left( {1996 + 2} \right).\left( {2000 - 2} \right)\\
= 1996.2000 - 2.1996 + 2.2000 - 2.2\\
= 1996.2000 + 2.\left( {2000 - 1996} \right) - 4\\
= 1996.2000 + 2.2 - 4\\
= 1996.2000 + 4 - 4\\
= 1996.2000\\
\Rightarrow E = F
\end{array}$
