题目

一个数除以3余2,除以5余3,除以7余2,求符合条件的最小数. 答案:【答案】23【解析】先列出除以3余2的数:2, 5, 8, 11, 14, 17, 20, 23, 26,…,再列出除以5余3的数:3, 8, 13, 18, 23, 28,….这两列数中,首先出现的公共数是8。3与5的最小公倍数是15。两个条件合并成一个就是8+15×整数,列出这一串数是8, 23, 38,…再列出除以7余2的数2, 9, 16, 23, 30, There _________ be a factory here. But it was pulled down last year. A. use to                      B. used to                     C. will    
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