r*****t 发帖数: 286 | 1 ☆─────────────────────────────────────☆
pen (谢谢你) 于 (Tue May 15 04:55:31 2007) 提到:
恩, 就是不给俺reimburse那个
有人问, 就放这儿吧
反正他们没让签不许透露题目的协议
math written test
bus arrives at 4, 10, 14, 20, ... , 54, 60 mins past each hour.
assume arrival time is random (uniform). what's the exp and var of
the waiting time?
put 18 balls into 10 boxes, expected # of empty boxes = ?
derivative of (ln x)^(ln x), \int ln(x) dx
consider the sun and a 1800 ft high building. angle between sun light
and ground is 45 degrees ( |
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