发新话题
打印【有0个人次参与评价】

[数学] 数学题求助

数学题求助

2004 students arrange themselves in a row.
In the first round of counting, they number themselves
  1, 2, 3, 1, 2, 3, 1, 2, 3 … from left to right.
In the second round of counting, they number themselves
  1, 2, 3, 4, 5, 1, 2, 3, 4, 5, 1, 2, 3, 4, 5,…  from right to left.
Find the number of students whose sum of numbers in the first and
second rounds of counting is 5..

TOP

402.

TOP

回复 2#阿弥陀佛 的帖子

谢谢阿弥陀佛,能给解题过程吗?.

TOP

因为[3,5]=15

所以共有[2004/15]x3+3=402.

TOP

发新话题