返回题库

HMMT 十一月 2008 · GEN1 赛 · 第 2 题

HMMT November 2008 — GEN1 Round — Problem 2

专题
Discrete Math / 离散数学
难度
L3
来源
HMMT

题目详情

  1. [ 3 ] What is the units digit of 7 ?
解析
  1. [ 3 ] What is the units digit of 7 ? 1 2 3 4 5 6 Answer: 7 Note that the units digits of 7 , 7 , 7 , 7 , 7 , 7 , . . . follows the pattern 7 , 9 , 3 , 1 , 7 , 9 , 3 , 1 , . . . . The 2009th term in this sequence should be 7. 4 4 502 Alternate method: Note that the units digit of 7 is equal to 1, so the units digit of (7 ) is also 4 502 2008 2008 2009