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IrinaOK
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Books, remainders 03 Sep 2007, 01:41
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ds



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ywilfred
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Books, remainders 03 Sep 2007, 01:57
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St1:
n = 7q2 + 1 where q2 is the number of rows in each stack

so 5q1+1 = 7q2+1, 5q1 = 7q2. q1 could be 7 (total number of books = 36), 14 (total number of books 71)...etc. Insufficient.

St2:
n = 8q3 + 4
5q1+1 = 8q3+4
5q1 = 8q3+3
q1 = (8q3+3)/5. --> 8q3 + 5 must be a multiple of 5.
valid value of q3 = 4, 9 ... and corresponding values of q1 = 7 (total number of books = 36), q1 = 15 (total number of books = 76)...etc..Insufficient.

Using both st1 and st2,
5q1 = 7q2
q1 = 7q2/5 ----[1]

7q2/5 = (8q3+3)/5
q2 = q3+3 --- [2]

q1 = (7q3+21)/5

q3 = 2, 7... then q1 = 7 (total number of books 36), 14 (total number of books = 71)...etc
Insufficient.

Ans E
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IrinaOK
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Books, remainders 03 Sep 2007, 11:19
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ywilfred
St1:
n = 7q2 + 1 where q2 is the number of rows in each stack

so 5q1+1 = 7q2+1, 5q1 = 7q2. q1 could be 7 (total number of books = 36), 14 (total number of books 71)...etc. Insufficient.

St2:
n = 8q3 + 4
5q1+1 = 8q3+4
5q1 = 8q3+3
q1 = (8q3+3)/5. --> 8q3 + 5 must be a multiple of 5.
valid value of q3 = 4, 9 ... and corresponding values of q1 = 7 (total number of books = 36), q1 = 15 (total number of books = 76)...etc..Insufficient.

Using both st1 and st2,
5q1 = 7q2
q1 = 7q2/5 ----[1]

7q2/5 = (8q3+3)/5
q2 = q3+3 --- [2]

q1 = (7q3+21)/5

q3 = 2, 7... then q1 = 7 (total number of books 36), 14 (total number of books = 71)...etc
Insufficient.

Ans E
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Got it,

I do not what made me think so, I thought if it takes q1 rows when each is 5, then it must take (q1-1) when each row has 7...
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skkingdom
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Books, remainders 04 Sep 2007, 14:12
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IrinaOK
ywilfred
St1:
n = 7q2 + 1 where q2 is the number of rows in each stack

so 5q1+1 = 7q2+1, 5q1 = 7q2. q1 could be 7 (total number of books = 36), 14 (total number of books 71)...etc. Insufficient.

St2:
n = 8q3 + 4
5q1+1 = 8q3+4
5q1 = 8q3+3
q1 = (8q3+3)/5. --> 8q3 + 5 must be a multiple of 5.
valid value of q3 = 4, 9 ... and corresponding values of q1 = 7 (total number of books = 36), q1 = 15 (total number of books = 76)...etc..Insufficient.

Using both st1 and st2,
5q1 = 7q2
q1 = 7q2/5 ----[1]

7q2/5 = (8q3+3)/5
q2 = q3+3 --- [2]

q1 = (7q3+21)/5

q3 = 2, 7... then q1 = 7 (total number of books 36), 14 (total number of books = 71)...etc
Insufficient.

Ans E

Got it,

I do not what made me think so, I thought if it takes q1 rows when each is 5, then it must take (q1-1) when each row has 7...
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sorry ywilfred but i dont get it... i think you made a mistake in the following transformation:

7q2/5 = (8q3+3)/5
q2 = q3+3 --- [2]

a book number of 71 which you mention for the statements combine does not fulfill the requirement / statement (2)
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skkingdom
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Books, remainders 04 Sep 2007, 14:27
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ywilfred with all your equations combining I always get 0=0 at the end...

does that proof that there is an infinite number of possibilities??
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IrinaOK
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Books, remainders 05 Sep 2007, 10:42
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skkingdom
ywilfred with all your equations combining I always get 0=0 at the end...

does that proof that there is an infinite number of possibilities??
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Skkingdom,

I have noticed that DS does time from time give unreaslistic results, like number of book is minus 3, ....

The point is that it is DS, as long as information provided is enough to asnwer Yes/No, one single value or do not remember the other type of asnwer now...the statement should be labeled SUFF , otherwise INSSUFF.

Please correct me if this observation is wrong...
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Books, remainders 05 Sep 2007, 10:56
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i think ans is C

cuz d only value v get wen v combine both is 36.



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
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