Data Sufficiency

Of the 1400 college teachers surveyed, 42 percent said that they considered engaging in research an essential goal. How many of the college teachers surveyed were women?

A. In the survey, 36 percent of the men and 50 percent of the women said that they considered engaging in research an essential goal

B. In the survey, 288 men said that they considered engaging in research an essential goal.

Answer: A

Please be kind enough to show your thought process.

x+y=1400
.36x + .5y = .42 * 1400

Multiply 2nd equation by 2 and subtract from the 1st. We get x. Then we can find y. That's why the answer is A

why not D ?

The answer is D.

for proving second statement as the answer

42 percent of 1400 is 588 teachers.

statement says that 288 of them are men.

So, number of women is 300.

Wonder why OA has been blacked out.

Thanks for the response. OA is A.

The answer has not been blacked out. It is called a spoiler. Please scroll your mouse over the answer to see what is says.

I got A using the MGMAT method (the chart from the Word Translaions book).
It looks like a lot but it only takes a few seconds to write out. And I hope my chart makes sense.

(1)
.............. Engaging........Not Engaging.........Total
Women .. .5W ........ .5W .................... W
Men ........ .36M ........ .64M................... M
Total ...... .42(1400) .. .58(1600) ............ 1400

Using the chart you can see that you could use formulas for the engaging and not engaging columns to figure out W. Sufficient.

(2)
.............. Engaging........Not Engaging.........Total
Women . .42(1400)-288 . ..........................
Men ........ 288 ........ ......................
Total ...... .42(1400) .. .58(1600) ............. 1400

We want to figure out how many total women, but we obviously don't have enough information given in the problem. You can see this because we would either need information about the total men, or the number of women/men not engaged in research to fill in the total women column. Insufficient.

Therefore answer is A.

PussInBoots wrote:x+y=1400
.36x + .5y = .42 * 1400

Multiply 2nd equation by 2 and subtract from the 1st. We get x. Then we can find y. That's why the answer is A

Dont solve!! simply one can see, that we will have he values of X and Y with the solution of the different equations.
(solve value of linear equation of 2 variables)

for choice 2 well we are not able to make a second equation and hence the linear equation of 2 varaibles is not solvable...

simple, the answer is A.

arora007 is right! One of the best things that you can do to improve your data sufficiency accuracy and efficiency is to recognize what will be sufficient without having to go through the process.

This is especially important with number properties. You should have the different properties down pat. When is x > x^2? If x^2 > y^2 is x > y? What numbers does x/2 is not an even number exclude? These are just examples.

It important for all of the various types of problems that you understand what information is necessary and what is not. To this end I recommend that when you finish solving a problem solving question that you then say, "what if this were data sufficiency?" How would this question be presented? What information do I need? This is quite useful because a problem solving question contains just the right amount of information needed in order to solve it and this can help you to see what is needed for data sufficiency.