Hi Celestial09,
In many DS questions, you might find it easier to get the question correct if you change the way that you "see" the question. Instead of saying/thinking "we don't know _____, so the Fact must be insufficient", try thinking this... "we don't have much information, but what COULD happen if I include the information in the Fact." In this way, you'll be seeking out the possibilities, which is a big part of what DS questions are testing you on.
In this prompt, we're told that there are 4 workers. In Fact 2, we're told that "No two workers sold the same number of shirts." What COULD this mean.....?
At the very least, since the 4 works sold DIFFERENT numbers of shirts, we would have....
0, 1, 2 and 3 shirts sold.
This means that at least one of them sold 3 (or more) shirts and the total sold is at least 6.
There are other possibilities, of course, but all of them are "bigger" than this one...
For example,
0, 1, 2, 5
1, 2, 3, 4
100, 101, 201, 598
Etc.
DS questions test many different skills, so be prepared to do WORK on each DS question. The good news is that the work is usually pretty easy; the bad news is that you MUST do the work if you want to be sure that you're choosing the correct answer.
GMAT assassins aren't born, they're made,
Rich
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