There 3 kinds of books in the library physics, chemistry and

Question

There 3 kinds of books in the library physics,chemistry and biology. Ratio of physics to chemistry is 3 to 2; ratio of chemistry to biology is 4 to 3, and the total of the books is more than 3000?which one of following can be the total of the book?

A. 3003
B. 3027
C. 3024
D. 3021
E. 3018

A. 3003 
B. 3027 
C. 3024 
D. 3021 
E. 3018

Bunuel · Answer

Given: P:C=3:2 and C:B=4:3. Equate C's by finding the LCM of 2 and 4 so that to be able to write down one ratio for all three kinds of books: P:C=6:4 and C:B=4:3 --> P:C:B=6:4:3. Now, 6+4+3=13, which means that we have total of 13 parts, thus the total number must be divisible by 13, only answer divisible by 13 is 3003.

Answer: A

Economist · Answer

True.

P:C = 3:2, C:B = 4:3 ( multiply P:C by 4 and C:B by 2 so that we have same C )
P:C = 12:8, C:B = 8:6
P:C:B = 12:8:6 = 6:4:3
6x+4x+3x= total =13x, so the total number of books should be divisible by 13, only 3003 is a possibility.

unceldolan · Answer

First, you have to find the common ratio for all 3 books. You have:
P:C:B 
3:2 --> multiply by 2 (gives you row 3) 
 4:6 
6:4:3

Hence:
P:C:B:T(Total)
6:4:3:13 ----> This means, the Total Number must be a multiple of 13.

Answer A is correct since 299 is divisible by 13, hence is 2990 and so is 3003 (2990+13).

saroshgilani · Answer

Bunuel  if p/c=3/2 .... i.e 2p=3c
and c/b=4/3 .... i.e 3c=4b.
why cant we say that, 2p=3c=4b?
what am i missing here?

AryamaDuttaSaikia · Answer

Yes we can say that - 2p= 3c=4b . In order to calculate the total no of books, we need to find the add all of the same parameters (by taking one book as "x") In this case (considering this relation) - all the variables add upto "13 parts" .

Find the "lowest common positive multiple" of 2,3,4. Answer will be 12. And then represent every variable accordingly. This calculation will lead to

6+4+3= 13 parts.

mvictor · Answer

P:C = 3:2
C:B = 4:3
P:C:B = 6:4:3

so we have 6+4+3 parts, or total 13 parts.
the answer must be a multiple of 13.
1300 is a multiple of 13
2600 is a multiple of 13
390 is a multiple of 13
add 2600 and 390
2990 is a multiple of 13.
2990+13 = 3003. multiple of 13. A works.
3003+13 = 3016. 3016+13 = 3029
as we can see, there are no other options but A.

bumpbot · Answer

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There 3 kinds of books in the library physics, chemistry and

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