Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Of the 75 houses in a certain community, 48 have a patio. [#permalink]
21 Feb 2008, 12:37

3

This post received KUDOS

2

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

55% (hard)

Question Stats:

36% (01:39) correct
64% (00:43) wrong based on 150 sessions

Of the 75 houses in a certain community, 48 have a patio. How many of the houses in the community have a swimming pool?

(1) 38 of the houses in the community have a patio but do not have a swimming pool. (2) The number of houses in the community that have a patio and a swimming pool is equal to the number of houses in the community that have neither a swimming pool nor a patio.

Re: GMATprep - Matrix [#permalink]
26 Feb 2008, 06:27

1

This post received KUDOS

bmwhype2 wrote:

Of the 75 houses in a certain community, 48 have a patio. How many of the houses in the community have a swimming pool?

(1) 38 of the houses in the community have a patio but do not have a swimming pool. (2) The number of houses in the community that have a patio and a swimming pool is equal to the number of houses in the community that have neither a swimming pool nor a patio.

finally can got my computer log in for work... so I can participate on GClub when I have nuffin to do.

Tricky problem. This is why its important to write everything out and not do it in your head.

youl notice we want x+z, which = m.

notice carefully that x+z also =27... its that simple, but so easy to miss... I missed it and said C at first.

Re: GMATprep - Matrix [#permalink]
26 Feb 2008, 13:14

GMATBLACKBELT wrote:

bmwhype2 wrote:

Of the 75 houses in a certain community, 48 have a patio. How many of the houses in the community have a swimming pool?

(1) 38 of the houses in the community have a patio but do not have a swimming pool. (2) The number of houses in the community that have a patio and a swimming pool is equal to the number of houses in the community that have neither a swimming pool nor a patio.

finally can got my computer log in for work... so I can participate on GClub when I have nuffin to do.

Tricky problem. This is why its important to write everything out and not do it in your head.

youl notice we want x+z, which = m.

notice carefully that x+z also =27... its that simple, but so easy to miss... I missed it and said C at first.

B

hmmm very tricky. we dont even need to know what z is. just M... _________________

You tried your best and you failed miserably. The lesson is 'never try'. -Homer Simpson

Re: GMATprep - Matrix [#permalink]
31 Dec 2009, 09:19

6

This post received KUDOS

Here is my standard approach to solve such problems P= # of houses with patio only. Q= # of houses with pool only. R= # of houses with patio & pool. S= # of houses with no patio & no pool.

Given P+Q+R+S=75 & P+R=48 What is Q+R? (1)

Solving the first two equations Q+S+48=75 Q+S=27 (2)

Now let's look at the statements Statement 1 P=38 unnecessary and insufficient.

Statement 2 R=S Substituting in (1) Q+S? We know form (2) that Q+S=27 hence sufficient. _________________

Re: Of the 75 houses in a certain community, 48 have a patio. [#permalink]
09 Jan 2014, 03:49

We have a universal formula: Total= A + B - Both(A&B) + Neither

(1) is obviously insufficient.

(2) is sufficient because from the given conditions we get this: Both(A&B) = Neither = T(Let it be T, to make it simple) => 75 = 48 + B - T + T => B = 27.

The best answer is B!

gmatclubot

Re: Of the 75 houses in a certain community, 48 have a patio.
[#permalink]
09 Jan 2014, 03:49