Concept

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Concept

by [email protected] » Wed Apr 02, 2014 10:30 pm
Please help me with the logic-Thanks
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by [email protected] » Wed Apr 02, 2014 11:42 pm
Hi Shibriz,

This DS question has an interesting limitation worth noting: there are 6 countries but no two countries sent the SAME number of representatives. There are 75 reps, but the six numbers that add up to 75 must be DIFFERENT. We're told that Country A sent the 2nd greatest number of reps. We're asked if Country A sent at least 10 reps. This is a YES/NO question.

Fact 1: One country sent 41 reps.

So, if 1 country sent 41 reps, the other 5 countries sent 34 reps. HOW can you get to 34 reps with 5 different numbers?

Let's say that Country A is the biggest of the 5 remaining countries....
The numbers could be 9, 8, 7, 6, 4 and the answer to the question is NO.
The numbers could be 10, 8, 7, 6, 3 and the answer to the question is YES.
Fact 1 is INSUFFICIENT.

Fact 2: Country A sent fewer than 12 reps.

The same examples that work in Fact 1 will work here...

If 1 country sent 41 reps...
Country A could have sent 9 reps and the answer to the question is NO.
Country A could have sent 10 reps and the answer to the question is YES.
Fact 2 is INSUFFICIENT.

Combined, we know that Country A could have sent 9 reps (NO answer) or 10 reps (YES answer).
Combined, INSUFFICIENT.

Final Answer: E

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by dakrownie » Sat Apr 05, 2014 6:21 am
Dear Rich,

How do you know when to use the same examples (sample numbers) for statement 1 and 2?

I normally avoid doing this so that I am able to isolate the statements, but what you have done with this question is really smooth. Please show us how

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by [email protected] » Sat Apr 05, 2014 1:21 pm
Hi dakrownie,

In DS questions, the two statements/Facts will NOT contradict one another, so there's always going to be a specific value (or values) that fit both.

Procedurally, you should deal with each statement on its own, but there is an interesting pattern that you can exploit. If you end up TESTing Values (which works well on most DS questions), and you keep your tests simple, then you'd be amazed how often the "overlap" will occur naturally.

In this question, we're told to focus on Country A (which we're also told sent the SECOND GREATEST number of reps). Fact 1 tells us that one country sent 41 reps (which could NOT have been Country A since there were only 75 reps in total and 41 is more than half). Fact 2 tells us the upper limit for Country A.

In other words...Fact 1 tells us about a country OTHER THAN A. Fact 2 tells us about COUNTRY A. Most (if not all) of the Tests that you could run for Fact 1 could be applied to Fact 2 because the two pieces of information talk about different subjects within the larger question.

You'll find that this process becomes easier as you practice more. For now, make sure that you take lots of notes and that you assemble to simplest, most obvious examples that you can for Fact 1. Look to immediately use whichever ones also fit Fact 2 and then do whatever additional work is required to prove the correct answer.

GMAT assassins aren't born, they're made,
Rich
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