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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

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:

Is the probability of drawing a 3 from a bag of numbered tiles greater than 50%?

(1) There is a 50% probability of drawing any number other than 3 from the bag. (2) The probability of drawing two threes is 0.

Hi,

The PROBABILITY will depend on .. A) number of 3s B) number of total balls OR C) ratio of 3s to rest

Let's see the statements... (1) There is a 50% probability of drawing any number other than 3 from the bag. This gives us the ratio between 3 and rest..50% so prob=1/2 Also P(3)+P( not 3)=100%.....P(3)+50%=100%......P(3)=50%=1/2 Sufficient

(2) The probability of drawing two threes is 0. This only means that there is ONLY one 3 in the box Insufficient

Re: Is the probability of drawing a 3 from a bag of numbered tiles greater [#permalink]

Show Tags

07 May 2017, 22:33

Statement 1. Probability of drawing any number other than 3 = 50% which means tiles with number other than 3 constitute 50% of the total tiles. This means tiles with number '3' constitute 100-50 = 50% of the total tiles. So Probability in this case = 50%, which is NOT greater than 50%. The answer is NO. Hence Sufficient.

Statement 2. If there are say 'n' 3's in the box and total number of tiles is say 'm', then probability of drawing two 3's: P = n/m * (n-1)/(m-1) This is given to be zero which means n(n-1) = 0. n is thus either 0 or 1. So there are either 0 or 1 tiles in the box having number 3

We don't know the total number of tiles in the box. If there are only two total tiles in the box (m=2) then if n=0, probability would be 0 but if n=1, probability would be 50% (still NOT greater than 50%).

If there is a single tile in the box (m=1) then in any case we cannot draw two 3's from the box so probability would be 0 (still NOT greater than 50%).

If there are three tiles (m=3) then if n=0, probability would be 0 but if n=1, probability would be 1/3 or 33.33% (still NOT greater than 50%).

With increasing values of m, probability would keep on decreasing.. But it will always stay less than 50% as you can see.

The answer is NO. Statement is Sufficient to answer.

Re: Is the probability of drawing a 3 from a bag of numbered tiles greater [#permalink]

Show Tags

22 May 2017, 04:36

And i would like to add:

You can actually make 2 things up from statement 2. If the chance of two times getting a 3 is 0, then one scenario would be that only one three exists OR no three exists.

Re: Is the probability of drawing a 3 from a bag of numbered tiles greater [#permalink]

Show Tags

08 Jun 2017, 10:31

chetan2u wrote:

Bunuel wrote:

Is the probability of drawing a 3 from a bag of numbered tiles greater than 50%?

(1) There is a 50% probability of drawing any number other than 3 from the bag. (2) The probability of drawing two threes is 0.

Hi,

The PROBABILITY will depend on .. A) number of 3s B) number of total balls OR C) ratio of 3s to rest

Let's see the statements... (1) There is a 50% probability of drawing any number other than 3 from the bag. This gives us the ratio between 3 and rest..50% so prob=1/2 Also P(3)+P( not 3)=100%.....P(3)+50%=100%......P(3)=50%=1/2 Sufficient

(2) The probability of drawing two threes is 0. This only means that there is ONLY one 3 in the box Insufficient

A

Hello Chetan, How can we say that there is only one three, there may be NIL threes...NO??

For Statement 2, it needs to be clear how we're drawing the two tiles - with replacement, or without? If we're drawing with replacement, and the probability of getting two threes is zero, then there are no threes in the bag, so the answer to the question is 'no', and the statement is sufficient.

If we're drawing without replacement, again we may have zero threes in the bag (in which case the answer is 'no'), or we may have exactly one three. But if there's only one three in the bag, and you pick one tile, the probability of picking a three will be 1/n, where n is the total number of tiles. This will only be greater than 50% if n is exactly 1. But the wording of the question (a bag of numbered tiles) suggests that there is more than one tile in the bag. So the pluralization of 'tiles' in the question stem suggests to me that we are meant to rule out the possibility there is only one tile in total, and that would make Statement 2 sufficient also.

But I wouldn't really know how to answer the question, because it's ambiguous whether we should admit the possibility that there is exactly one tile in total in the bag of tiles.
_________________

GMAT Tutor in Toronto

If you are looking for online GMAT math tutoring, or if you are interested in buying my advanced Quant books and problem sets, please contact me at ianstewartgmat at gmail.com

Re: Is the probability of drawing a 3 from a bag of numbered tiles greater [#permalink]

Show Tags

25 Jul 2017, 11:17

I got D

1. The P (drawing 3) + P (not drawing 3) = 1

so we get .5 + x = 1 so x = .5 Therefore the probability of drawing a 3 is not greater than 50% - statement 1 is sufficient

2. It states that the probability of drawing multiple 3's is 0 which indicates that there is only one 3 in the bag. The question prompt describes a "bag of tiles" so we know that there is at least two tiles in the bag. therefore the probability of drawing a 3 is less than or equal to 50%. statement 2 is sufficient

Re: Is the probability of drawing a 3 from a bag of numbered tiles greater [#permalink]

Show Tags

13 Aug 2017, 01:11

Jimbo1912 wrote:

I got D

1. The P (drawing 3) + P (not drawing 3) = 1

so we get .5 + x = 1 so x = .5 Therefore the probability of drawing a 3 is not greater than 50% - statement 1 is sufficient

2. It states that the probability of drawing multiple 3's is 0 which indicates that there is only one 3 in the bag. The question prompt describes a "bag of tiles" so we know that there is at least two tiles in the bag. therefore the probability of drawing a 3 is less than or equal to 50%. statement 2 is sufficient

You got the first statement correct.

The second statement says that the probability of drawing two threes is 0. But we don't know whether there are any tiles numbered 3 or whether there is a single tile with number 3. So, statement 2 is not sufficient.

Re: Is the probability of drawing a 3 from a bag of numbered tiles greater [#permalink]

Show Tags

22 Aug 2017, 10:40

Bunuel wrote:

Is the probability of drawing a 3 from a bag of numbered tiles greater than 50%?

(1) There is a 50% probability of drawing any number other than 3 from the bag. (2) The probability of drawing two threes is 0.

(1) Tells us that the probability that a 3 will NOT be drawn from the bag is 50%. Hence the probability that a 3 is drawn from the bag is also 50% Sufficient

(2) Tells us that there is either one or no 3 in the bag. Insufficient

We’ve given one of our favorite features a boost! You can now manage your profile photo, or avatar , right on WordPress.com. This avatar, powered by a service...

Sometimes it’s the extra touches that make all the difference; on your website, that’s the photos and video that give your content life. You asked for streamlined access...

A lot has been written recently about the big five technology giants (Microsoft, Google, Amazon, Apple, and Facebook) that dominate the technology sector. There are fears about the...

Post today is short and sweet for my MBA batchmates! We survived Foundations term, and tomorrow's the start of our Term 1! I'm sharing my pre-MBA notes...