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Getting confused with data efficiency

Expert replies
by doctortt » Wed Feb 18, 2009 6:26 am
I'm very confused with data efficiency questions. I know the goal is to determine whether the conditions are sufficient to answer the question and not to find the answer of the question. Sometimes, I see that a condition is not sufficient, but it's indeed sufficient when I check the answer. Especially those odd and even data efficiency questions, I get them wrong all the time. I must be missing something. Please help.
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Source: — Data Sufficiency |

Re: Getting confused with data efficiency

by xyz21 » Mon Feb 23, 2009 9:33 am
doctortt wrote:I'm very confused with data efficiency questions. I know the goal is to determine whether the conditions are sufficient to answer the question and not to find the answer of the question. Sometimes, I see that a condition is not sufficient, but it's indeed sufficient when I check the answer. Especially those odd and even data efficiency questions, I get them wrong all the time. I must be missing something. Please help.
Search the board for DS Strategy
Also, it might be helpful to buy mgmat guides on the relevant topics. They have great DS approach (AD/BCE method, which you can find somewhere online as well)
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