400-880-6200
专家免费评估 留学案例 雅思保分 免费备考资料 留学热线 400-880-6200

AMC10每日一题(2001年真题#08)

  • 2018-05-22     
  • 801 人浏览
  • 分享
  • 收藏

2001 AMC 10 竞赛试题/第08题


Problem

Wanda, Darren, Beatrice, and Chi are tutors in the school math lab. Their schedule is as follows: Darren works every third school day, Wanda works every fourth school day, Beatrice works every sixth school day, and Chi works every seventh school day. Today they are all working in the math lab. In how many school days from today will they next be together tutoring in the lab?

$\textbf{(A) }42\qquad\textbf{(B) }84\qquad\textbf{(C) }126\qquad\textbf{(D) }168\qquad\textbf{(E) }252$


Solution

We need to find the least common multiple of the four numbers given. That is, the next time they will be together. First, find the least common multiple of $3$ and $4$.

$3 \times 4 = 12$.

Find the least common multiple of $12$ and $6$.

Since $12$ is a multiple of $6$, the least common multiple is $12$.

Lastly, the least common multiple of $12$ and $7$ is $12 \times\ 7 = \boxed{\textbf{(B) }84}$.


 . '文章底图' .
课窝考试网(http://www.ikewo.cn)声明

本站凡注明原创和署名的文章,未经课窝考试网许可,不得转载。课窝考试网的部分文章素材来自于网络,版权归原作者所有,仅供学习与研究,如果侵权,请提供版权证明,以便尽快删除。

专家答疑
  • 点击刷新验证码
  • 获取验证码
确认提交
在线咨询
扫一扫获取最新考试资讯
400-880-6200
立即咨询
二维码
二维码
回到顶部