特级会员
We have, 3x + 2 = n 5y + 1 = n (x & y being their respective quotient) Therefore, 3x + 2 = 5y + 1 3x = 5y - 1 x = (5y - 1)/3 Now we know that, 5y - 1 is divisible by 3, so lets substitute y = 0, 1, or 2 Trying these values we find y = 2 3x = 5(2) - 1 3x = 9 x = 3 n = 3x + 2 = 9 + 2 = 11 n = 5y + 1 = 10 + 1 = 11 Thus 11 is the least possible value of n
使用道具 举报
中级会员
阿之 发表于 2017-7-19 06:24 我的解法的话: 因为是5的倍数+1:第一个是5*1+1 = 6,但是6/3=2,不满足第一条件; 第二个是5*2+1 = 11, ...
发表回复 回帖后跳转到最后一页