meili 发表于 2022-10-27 15:46:07

几道数学填空题.1.40比()少3/2023比()多1/421/2+1/6+1/12+1/20+1/30+1/42+1/52+1/72+1/90(这类题怎么做啊?有没有简便算法?)=3.数字迷(乘法的那种)怎么做啊?

<p>问题:几道数学填空题.1.40比()少3/2023比()多1/421/2+1/6+1/12+1/20+1/30+1/42+1/52+1/72+1/90(这类题怎么做啊?有没有简便算法?)=3.数字迷(乘法的那种)怎么做啊?
<p>答案:↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">宋昕的回答:<div class="content-b">网友采纳  1.40比(40又3/8)少3/8  120比(119又3/4)多1/4  2.1/2+1/6+1/12+1/20+1/30+1/42+1/52+1/72+1/90  =1/(1*2)+1/(2*3)+1/(3*4)+...+1/(8*9)+1/(9*10)  =(1/1-1/2)+(1/2-1/3)+(1/3-1/4)+...+(1/8-1/9)+(1/9-1/10)  =1-1/10  =9/10  3.暂时还没想到,不好意思哦.
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查看完整版本: 几道数学填空题.1.40比()少3/2023比()多1/421/2+1/6+1/12+1/20+1/30+1/42+1/52+1/72+1/90(这类题怎么做啊?有没有简便算法?)=3.数字迷(乘法的那种)怎么做啊?