Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.
Of the 1400 college teachers surveyed, 42% said they considered engaging in research an essential goal. How many of the college teacher surveyed were women?
(1) In the survey 36% of men and 50% of women said that they consider engaging in research activity an essential goal.
(2) In the survey 288 men said that they consider engaging in research activity an essential goal.
If we modify the original condition, we can get a '2by2' table, which is one of the most common types of question in GMAT Math
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GC DS burmttwinky Of the 1400 college.png [ 3.6 KiB | Viewed 43676 times ]
When looking at the table, we can see that a+b+c+d=1400, a+b=1400*42%.
There are 4 variables and 2 equations, so we need 2 more equations
From condition 1, there are 2 equations (b=0.36(b+d), a=0.5(a+c)), so this is sufficient,
whereas condition 2 only gives one condition (b=288), making this insufficient and the answer becomes (A).