2003年3月JJ21,26

dajiqi

21) @ can be indicated plus, subtract, and product. what's the value of 1@0? a. 0@2= 2
b. 2@0= 2 A; A
Answer: A

26) 53 is the standard deviation of T(一数列) greater than S(一数列) ?
(1) mean of T is greater than that of S
(2) median of T is greater than that of S
Answer: A


    


晕菜菜... 21题为什么不是D呢?         B中的2+0, 2-0 都不影响1@0呀??


26题晕晕菜菜...我觉得应该是D


请教各位??

donna

以下是引用dajiqi在2004-2-26 15:27:00的发言：
21) @ can be indicated plus, subtract, and product. what's the value of 1@0? a. 0@2= 2
b. 2@0= 2 A; A
Answer: A

26) 53 is the standard deviation of T(一数列) greater than S(一数列) ?
(1) mean of T is greater than that of S
(2) median of T is greater than that of S
Answer: A



    


晕菜菜... 21题为什么不是D呢?         B中的2+0, 2-0 都不影响1@0呀??


26题晕晕菜菜...我觉得应该是D


请教各位??

21，应该是D


26，是E，因为标准方差和中数无关，只和每个数与平均数的偏差有关。请看我总结中的标准方差的总结：dispbbs.asp?boardID=22&ID=38109&page=1

dajiqi

多谢斑竹的解惑.