BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Manhattan Ds

Expert replies
by venmic » Sun Jan 15, 2012 11:18 pm
If Pool Y currently contains more water than Pool X, and if Pool X is currently filled to 2/7 of its capacity, what percent of the water currently in Pool Y needs to be transferred to Pool X if Pool X and Pool Y are to have equal volumes of water?

(1) If all the water currently in Pool Y were transferred to Pool X, Pool X would be filled to 6/7 of its capacity.

(2) Pool X has a capacity of 14,000 gallons.

A
Join the discussion
Source: — Data Sufficiency |

by Anurag@Gurome » Sun Jan 15, 2012 11:31 pm
venmic wrote:If Pool Y currently contains more water than Pool X, and if Pool X is currently filled to 2/7 of its capacity, what percent of the water currently in Pool Y needs to be transferred to Pool X if Pool X and Pool Y are to have equal volumes of water?

(1) If all the water currently in Pool Y were transferred to Pool X, Pool X would be filled to 6/7 of its capacity.

(2) Pool X has a capacity of 14,000 gallons.

A
It is given that pool X has 2/7th of water.

(1) If all the water currently in Pool Y were transferred to Pool X, Pool X would be filled to 6/7 of its capacity. This means pool Y has 6/7 - 2/7 = 4/7 of water.
For Pool X and Pool Y are to have equal volumes of water, if we move 1/7 water from pool Y to pool X, then both the pools will have 3/7 of water; SUFFICIENT.

(2) Pool X has a capacity of 14,000 gallons but there is info on pool Y; NOT sufficient.

The correct answer is A.
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/
Join the discussion

by GMATGuruNY » Mon Jan 16, 2012 8:32 am
venmic wrote:If Pool Y currently contains more water than Pool X, and if Pool X is currently filled to 2/7 of its capacity, what percent of the water currently in Pool Y needs to be transferred to Pool X if Pool X and Pool Y are to have equal volumes of water?

(1) If all the water currently in Pool Y were transferred to Pool X, Pool X would be filled to 6/7 of its capacity.

(2) Pool X has a capacity of 14,000 gallons.

A
Statement 1: If all the water currently in Pool Y were transferred to Pool X, Pool X would be filled to 6/7 of its capacity.
Let the capacity of Pool X = 14 units.
Amount in Pool X = (2/7)*14 = 4 units.
After the transfer from Pool Y, the amount in Pool X = (6/7)*14 = 12 units. This is the total amount of water.
The amount transferred from Pool Y = 12-4 = 8 units.
In order for each pool to have the same amount -- 6 units -- 2 of the 8 units in Pool Y must be transferred to Pool X:
2/8 = 1/4 = 25%.

If we multiply the capacity of Pool X by a factor, all of the subsequent values will be multiplied by the SAME FACTOR, so the resulting percentage of Pool Y that must be transferred WILL REMAIN 25%.
SUFFICIENT.

Statement 2: Pool X has a capacity of 14,000 gallons.
No information about Pool Y.
INSUFFICIENT.

The correct answer is A.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Join the discussion