There are 75 bookshelves in the history section of a

Question

There are 75 bookshelves in the history section of a library. If the shelves are organized from the fewest books to the most books how many books are on the middle (median) shelf?

1)60% of the shelves have more than 50 books each
2)More than 55% of the shelves have less than 52 books each.


I had a tough time with this, have the right answer but don't understand it. Anyone wanna shed some light on this problem?

thearch · Answer

I pick C
and I dare say the number of the books is 51

Grant · Answer

Well can you elaborate on your thought process and how you obtained that answer?

murat · Answer

For 75 shelves, the median is at shelf 37.

1 - 60% of 75 shlef is 45 shelves. This is more than 37 therefore shelf 37
should have more than 50 books. This by itself is not sufficient.

2 - 55% of 75 is 41.25 say 41 or 42 shelves. This is still more than 37, which means shelf 37 will have books less than 52. This by itself is not sufficient.

Combine 1 and 2. The # of books in shelf 37 is = 50<#books<52.
51 is the only integer that will satisfy this requirement. Therefore answer is C.

700Plus · Answer

C.
Took a while to understand and figure the solution.
I dont think one neeeds to calculate what is half,55% or 60% of 75.

Combining 1 and 2 tells you that 55% of the shelves have books that are greater than 50 and less than 52.Meaning all these 55% of the shelves have 51 books each.

MA · Answer

ok, guys, i am going with E.
statement 2 says not 55% but more than 55% have less than 52 books. it means the 55% (41.25 equivalant to 41st sheleve) could belongs from 1 to 41 or from 5 to 46 or 30 to 71, we do nt know.

Grant · Answer

The correct answer is C.

HongHu · Answer

Note this phrase, MA.

There are 75 bookshelves in the history section of a

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