求教数学题 谢谢

GWD     Q17:

Box W and Box V each contain several blue sticks and red sticks, and all of the red sticks have the same length.  The length of each red stick is 18 inches less than the average length of the sticks in Box W and 6 inches greater than the average length of the sticks in Box V.  What is the average (arithmetic mean) length, in inches, of the sticks in Box W minus the average length, in inches, of the sticks in Box V?

A.    3

B.    6

C.    12

D.    18

E.    24

请问此题该用什么思路考虑?如果计算的话似乎很难算出来

是不是24啊？

不就是18-（-6）吗～

感觉没什么～

就是RED是标准，一个比丫大18，一个比丫小6，问差！