儿子的题,请教哪位知道怎么做?

For every letter, an alphabetized list has 3 words that begin with that letter. The word "SALE" could be the ? entry on the list.

A) 51st   B) 53rd    C) 54th     D) 56th

 

另一个题:

The ones' digit of the largest nine-digit perfect square is

A) 0    B) 1     C) 4     D) 9

谢谢!

所有跟帖： 

• 1/D, 2/C -*Peanuts*- ♀ (0 bytes) () 06/30/2012 postreply 10:14:29

• 第一题考虑S是字母表的第几个字母；第二题先求最小十位数的平方根，取整，再反算 -*Peanuts*- ♀ (0 bytes) () 06/30/2012 postreply 10:16:19

• 谢谢!第一题能不能展开说说? 我其实没看懂题 -studentdriver- ♀ (0 bytes) () 06/30/2012 postreply 10:19:47

• 每个字母打头有三个单词，S是第19个字母，所带的词是第55~57个，所以答案只能是56 -*Peanuts*- ♀ (0 bytes) () 06/30/2012 postreply 10:26:45

• 明白了,谢谢 -studentdriver- ♀ (0 bytes) () 06/30/2012 postreply 10:33:47

• 第二题因为不能用计算器,所以不知道是否有特别的方法 -studentdriver- ♀ (0 bytes) () 06/30/2012 postreply 10:21:04

• sqrt(10)=3.1623 so your answer is the last digit of sq of 31622 -Kamioka- ♀ (0 bytes) () 06/30/2012 postreply 11:01:56

• last digit of sq of 31622 is 4 -Kamioka- ♀ (0 bytes) () 06/30/2012 postreply 11:02:47

• thanks -studentdriver- ♀ (0 bytes) () 06/30/2012 postreply 11:07:34

• 这些题挺有意思的。他的老师从哪儿搞到的？ -calligraphy- ♂ (0 bytes) () 06/30/2012 postreply 18:46:36