问题 填空题

用简便方法计算:

503×497=______;1.02×0.98=______

答案

503×497,

=(500+3)(500-3),

=5002-32

=249991;

1.02×0.98,

=(1+0.02)(1-0.02),

=1-0.022

=0.9996.

故本题答案为:249991,0.9996.

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