the OA is B. Please explain!
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table question
the OA is B. Please explain!
- RonPurewal
- Students
- Posts: 19744
- Joined: Tue Aug 14, 2007 8:23 am
(1) alone:
obviously INSUFFICIENT, because we have no rule dictating how the table works.
(2) alone:
given all the Q's in the table, use this rule to fill in the other squares of the table in terms of Q. you can fill in the table from left to right and/or from top to bottom, following the rule repeatedly.
Q ..... Q ..... Q ..... Q
Q ... 2Q ... 3Q ... 4Q
Q ... 3Q ... 6Q ... 10Q
Q ... 4Q ... 10Q ... 20Q
as you can see, the bottom right square must contain 20Q, so it follows that Z must equal 20Q.
we don't have a numerical value for Z or Q unless we take both statements together, but note that this is immaterial: all that matters is the relationship between Z and Q, which is completely determined by (2) alone.
obviously INSUFFICIENT, because we have no rule dictating how the table works.
(2) alone:
given all the Q's in the table, use this rule to fill in the other squares of the table in terms of Q. you can fill in the table from left to right and/or from top to bottom, following the rule repeatedly.
Q ..... Q ..... Q ..... Q
Q ... 2Q ... 3Q ... 4Q
Q ... 3Q ... 6Q ... 10Q
Q ... 4Q ... 10Q ... 20Q
as you can see, the bottom right square must contain 20Q, so it follows that Z must equal 20Q.
we don't have a numerical value for Z or Q unless we take both statements together, but note that this is immaterial: all that matters is the relationship between Z and Q, which is completely determined by (2) alone.
- StaceyKoprince
- ManhattanGMAT Staff
- Posts: 9363
- Joined: Wed Oct 19, 2005 9:05 am
- Location: Montreal
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