1000DS section 8 #25

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Source: — Data Sufficiency |

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by shibal » Thu Jul 09, 2009 5:40 am
if r and s are integers, ou'd know the answer easily, however it doesn't say in the stem that r and s are both integers....
therefore A wouldn't be right...
wth stmt 2 it gives us the missing info, which enables us to get the answer....

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by rookiez » Thu Jul 09, 2009 6:29 am
yes its not mentioned in the question whether r/s are integers or fractions...but stmt 1 still should suffice...
from stmt 1 s - r = 5 which implies
i. conside r as a fraction r=3/4; hence s should be = 23/4 to satisfy s-r=5...and terefore we still can count how many integer 'n' are in between these 2 s & r
ii. s=17, r=12....hence 17-12=5...and hence we know how many integers are between these 2

still A

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by PumaJr » Thu Jul 09, 2009 6:37 am
rookiez wrote:yes its not mentioned in the question whether r/s are integers or fractions...but stmt 1 still should suffice...
from stmt 1 s - r = 5 which implies
i. conside r as a fraction r=3/4; hence s should be = 23/4 to satisfy s-r=5...and terefore we still can count how many integer 'n' are in between these 2 s & r
ii. s=17, r=12....hence 17-12=5...and hence we know how many integers are between these 2

still A
If r and s could either be fractions or integers, then n could equal 5 if r and s are fractions or 4 if r and s are integers. Insufficient. You need the information given in ii. to lock down which case it is.