用简便方法计算:503×497=______;1.02×0.98=______
题型:填空题难度:一般来源:不详
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. |
举一反三
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