In various competitions in our school’s art festival, the students of Grade 7 (1) achieved excellent results. In order to commend the students, Teacher Lin specially went to Ruian Bookstore

(1) Suppose you bought x copies of "Chinese Historical Stories" and y copies of "Famous Quotes".

From the question, x+y=2050×0.8x+ 20×0.8y=440,

The solution is x=5y=15.

Answer: I bought 5 copies of "Chinese Historical Stories" and 15 copies of "Famous Quotes";

(2) Suppose the three books are x, y, and z, from the meaning of the question

x+y+z＝2050×0.8x+20×0.8y+25×0.8z＝360

Eliminate z to get 20x-4y= -40

∴y=5x+10

∵x and y are both positive integers,

∴x=1y=15z=4.

So the answer is: 15.