Books

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Books

by aroon7 » Sun Jan 25, 2009 4:58 pm
In a class of 30 students, 2 students did not borrow any books from the library, 12 students each borrowed 1 book, 10 students each borrowed 2 books, and the rest of the students each borrowed atleast 3 books. If the average number of books borrowed per student was 2, what is the maximum number of books that any single student could have borrowed?

A) 3
B) 5
C) 8
D) 13
E) 15
Source: — Problem Solving |

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by awesomeusername » Sun Jan 25, 2009 5:37 pm
Took me over 2 minutes to solve this, but I got 13 with the same method as described in the linked thread above. Thanks for the good question.

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by gaggleofgirls » Sun Jan 25, 2009 5:39 pm
2(0) + 12(1) + 10(2) +x / 30 = 2
x = 28

The remaining 6 students checked out 28 and they each checked out at least 3, so if 5 of the 6 checked out only 3, then the 6th student checks out the maximum number of books.

5*3 = 15
28-15 = 13

The most books that one of the remaining students could check out is 13.

Answer = D

-carrie

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by aroon7 » Sun Jan 25, 2009 5:58 pm
Thanks Carrie...
i calculated (???) 30 - (2 + 12 + 10) as 16
nobody can save me! :oops:

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by gaggleofgirls » Sun Jan 25, 2009 6:00 pm
I have been making simple math mistakes myself, but the more I study, the less I do it. There is hope :)

-Carrie