Kindly share the Answers!
I believe they are 5/6 and 1/3
Hi, there. I'm happy to contribute here.
First of all, this question, and the OA, can be found at:http://www.mba.com/the-gmat/nex-gen/sam ... x?next=yes
This is from one of the "old" sample IR questions that GMAC released, so presumably not as representative of the IR section as the online material that accompanies the OG13.
I can guarantee the OAs are as follows:
1) If one student is selected at random from the 300 surveyed, the chance that the student will be under 30 or a high school graduate or both is 5/6
2) If one student is selected at random from the 300 surveyed, the chance that the student will be both under 30 and a high school graduate is 1/3
There are 30 "ticks" in the diagram --- for the first, we are including everyone except the folks who are over 30 and
have no high school diploma -- those would be the five ticks in the central overlap oval --- so the other 25 ticks are "legal" for the first question, and 25/30 = 5/6.
For the second question, we only want folks under thirty (outside of the right circle) and
have a HS diploma (outside the left circle also) --- so the only "legal' ticks are the row of 10 ticks hovering above both circles --- 10/30 = 1/3.
Does all that make sense?
Here's a link to a free IR eBook I wrote:http://magoosh.com/gmat/2012/gmat-integ ... ing-ebook/
I hope that helps. Let me know if anyone has any IR related questions.
Magoosh Test Prep