<PRE><B>Question 1184694</B>
Let x=total # of files, staples and books
(3/5)x = # of files
1/4(x-(3/5)x)=# of staples
(1/10)x=# of staples
x-((3/5)x+(1/10)x)=number of books
(3/10)x= # of books
and we are told that:
(1/10)x+10=(3/10)x
simplify:
2x=100
x=50 total # of files, staples and books
(3/10)x times 50=15 number of books
11 times 50 times 15= total mass of books
hope this helps 



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