Over a certain time period, did the number of shares of stock in Ruth's portfolio increase?
(1) Over the time period, the ratio of the number of shares of stock to the total number of shares of stocks and bonds in Ruth's portfolio increased.
(2) Over the time period, the total number of shares of stocks and bonds in Ruth's portfolio increased.
Curious to see how others get to the answer quickly. I simply used logic here and didn't do any computation.
OA is C.
5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
Shares of Stock in Ruth's Portfolio
This topic has expert replies
-
queenisabella
- Senior | Next Rank: 100 Posts
- Posts: 47
- Joined: Sun Feb 05, 2012 7:56 pm
- Followed by:3 members
-
Bill@VeritasPrep
- GMAT Instructor
- Posts: 1248
- Joined: Thu Mar 29, 2012 2:57 pm
- Location: Everywhere
- Thanked: 503 times
- Followed by:192 members
- GMAT Score:780
1) The ratio of shares:total could increase by adding more shares or by reducing the number of bonds. Insufficient.
2) The total number could increase by adding shares, adding bonds, or both. Insufficient.
Combined, we know the total number of shares and bonds went up, and we know the ratio of shares:total went up. The only way both statements can be true is if the number of shares increased. Thus, we need both statements.
2) The total number could increase by adding shares, adding bonds, or both. Insufficient.
Combined, we know the total number of shares and bonds went up, and we know the ratio of shares:total went up. The only way both statements can be true is if the number of shares increased. Thus, we need both statements.
Join Veritas Prep's 2010 Instructor of the Year, Matt Douglas for GMATT Mondays
Visit the Veritas Prep Blog
Try the FREE Veritas Prep Practice Test
Visit the Veritas Prep Blog
Try the FREE Veritas Prep Practice Test
GMAT/MBA Expert
-
Anurag@Gurome
- GMAT Instructor
- Posts: 3835
- Joined: Fri Apr 02, 2010 10:00 pm
- Location: Milpitas, CA
- Thanked: 1854 times
- Followed by:523 members
- GMAT Score:770
queenisabella wrote:Over a certain time period, did the number of shares of stock in Ruth's portfolio increase?
(1) Over the time period, the ratio of the number of shares of stock to the total number of shares of stocks and bonds in Ruth's portfolio increased.
(2) Over the time period, the total number of shares of stocks and bonds in Ruth's portfolio increased.
Curious to see how others get to the answer quickly. I simply used logic here and didn't do any computation.
OA is C.
Let us assume that number of shares = S and number of bonds = B
(1) Over the time period, the ratio of the number of shares of stock to the total number of shares of stocks and bonds in Ruth's portfolio increased implies S : (S + B) increased but this does not imply for sure if the number of shares of stock in Ruth's portfolio increased, it could be due decrease also; NOT sufficient.
(2) Over the time period, the total number of shares of stocks and bonds in Ruth's portfolio increased implies S + B increased but again this does not imply for sure if the number of shares of stock in Ruth's portfolio increased; NOT sufficient.
Combining (1) and (2), S + B increased and S : (S + B) increased, which is possible only if S is also increased; SUFFICIENT.
The correct answer is C.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)
Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)
Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
-
dhonu121
- Master | Next Rank: 500 Posts
- Posts: 316
- Joined: Sun Aug 21, 2011 6:18 am
- Thanked: 16 times
- Followed by:6 members
1 and 2 sufficient.Over a certain time period, did the number of shares of stock in Ruth's portfolio increase?
(1) Over the time period, the ratio of the number of shares of stock to the total number of shares of stocks and bonds in Ruth's portfolio increased. (r/r+d) increased. So either r increased or d decresed. Insuff.
(2) Over the time period, the total number of shares of stocks and bonds in Ruth's portfolio increased. (r+d) increasaed. Hence either of r or d could have increased. hence Insuff.
Using 1 and 2, r+d increased, hence for 1 to be true, r should have increased and not d.
Curious to see how others get to the answer quickly. I simply used logic here and didn't do any computation.
Hence C
If you've liked my post, let me know by pressing the thanks button.
