麵試問題請教

剛從一個公司麵試回來。有一問題沒有做出，請教這裏的高手：
有一塊草地，牛來吃草。吃的rate是一樣的。三隻牛可以吃3天，兩隻牛吃6天，問一隻牛可吃幾天？注意：草是在長的！

另外：在找工作，有一天，一“中介”來電，問了經曆，技術，背景，介紹了他有的位子，突然問“你的生日是那天”，當時警惕不高，猶豫中還是說了，以為是背景調查需要的。事後越想越不對。如果我懷疑他要盜用我的身份，怎樣預防呢？該與誰聯係？

謝謝諸位。

所有跟帖： 

• 好象一頭牛永遠也吃不完，不知道對不對 -撅著挺好- ♂ (0 bytes) () 05/03/2009 postreply 07:35:06

• 9天 -richard0920- ♀ (0 bytes) () 05/03/2009 postreply 18:50:16

• 回複：麵試問題請教 -streetwalker- ♂ (319 bytes) () 05/03/2009 postreply 09:21:58

• It's not that simple. -rubikscube- ♀ (287 bytes) () 05/03/2009 postreply 13:28:07

• my assumption is that a fixed size of lawn always grows the same -streetwalker- ♂ (269 bytes) () 05/03/2009 postreply 14:58:25

• My assumption is that that grass can't grow anymore -Rubikscube- ♀ (94 bytes) () 05/03/2009 postreply 15:24:54

• Forever. The key is to figure out the growth rate -Rubikscube- ♀ (910 bytes) () 05/03/2009 postreply 09:49:04

• 可以直接跟他說，簡曆裏都寫了生日了， -xtd- ♀ (0 bytes) () 05/03/2009 postreply 10:13:03

• 簡曆裏都寫了生日了？？？？ -wxc369- ♂ (28 bytes) () 05/03/2009 postreply 10:31:06

• 我來說說。 -sigma- ♂ (110 bytes) () 05/03/2009 postreply 10:34:30

• 你麵試什麽工作？ -雲河- ♀ (37 bytes) () 05/03/2009 postreply 11:03:17

• 或者是放高利貸的... -rubikscube- ♀ (213 bytes) () 05/03/2009 postreply 11:14:08

• IT. -WatchOnly- ♀ (0 bytes) () 05/03/2009 postreply 12:26:52

• Another way to look at this problem. -Rubikscube- ♀ (584 bytes) () 05/03/2009 postreply 12:49:01

• 這就是著名的牛頓吃草問題 -怪哉- ♂ (85 bytes) () 05/03/2009 postreply 13:22:36

• What' wrong with this? -0.0001- ♂ (285 bytes) () 05/03/2009 postreply 13:23:33

• 數字太高深,看不懂 -喜氣連年- ♀ (0 bytes) () 05/03/2009 postreply 14:23:35

• Surprising, isn't it? What' wrong with this? -戲雨飛鷹- ♀ (0 bytes) () 05/03/2009 postreply 14:27:43

• 一頭牛永遠吃不完這塊草！ -為了活著- ♂ (127 bytes) () 05/03/2009 postreply 17:12:06

• typical scenario in China--老牛吃嫩草，永遠吃不完 -撅著挺好- ♂ (0 bytes) () 05/03/2009 postreply 14:34:31

• 嗬嗬,嫩草一茬又一茬,春風吹又生 -喜氣連年- ♀ (0 bytes) () 05/03/2009 postreply 14:53:35

• exactly! -撅著挺好- ♂ (0 bytes) () 05/03/2009 postreply 15:01:40

• off the top of my head, the guy is so lucky, I'm kinda jealous,h -撅著挺好- ♂ (0 bytes) () 05/03/2009 postreply 18:37:58