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:

A certain deck of cards contains 2 blue cards, 2 red cards [#permalink]
05 May 2012, 02:08

3

This post received KUDOS

00:00

A

B

C

D

E

Difficulty:

5% (low)

Question Stats:

93% (01:47) correct
7% (00:39) wrong based on 28 sessions

A certain deck of cards contains 2 blue cards, 2 red cards, 2 yellow cards, and 2 green cards. If two cards are randomly drawn from the deck, what is the probability that they will both be not blue?

A. 15/28 B. 1/4 C. 9/16 D. 1/32 E. 1/16

Hi I have a confusion as to how to solve this question , if somebody can help me ?

Re: A certain deck of cards contains 2 blue cards, 2 red cards [#permalink]
05 May 2012, 02:26

3

This post received KUDOS

Expert's post

BhaskarPaul wrote:

A certain deck of cards contains 2 blue cards, 2 red cards, 2 yellow cards, and 2 green cards. If two cards are randomly drawn from the deck, what is the probability that they will both be not blue?

A. 15/28 B. 1/4 C. 9/16 D. 1/32 E. 1/16

Hi I have a confusion as to how to solve this question , if somebody can help me ?

The question is a bit ambiguous. I guess we are asked to find the probability that neither of the cards drawn is blue, if so then P=P(not blue)*P(not blue)=6/8*5/7=15/28.

Answer: A.

One can interpret the question as: what is the probability that we don't have (blue, blue) case then P=1-P(blue, blue)=1-2/8*1/7=27/28.

Re: A certain deck of cards contains 2 blue cards, 2 red cards [#permalink]
05 May 2012, 03:04

8

This post received KUDOS

Thanks Bunuel for the prompt response.

I quess the these two questions should clear the concept

1)Seven beads are in a bag: three blue, two red, and two green. If three beads are randomly drawn from the bag, what is the probability that NONEof them are blue?

answer: (4/7) x (3/6) x (2/5) = 4/35

2)Seven beads are in a bag: three blue, two red, and two green. If three beads are randomly drawn from the bag, what is the probability that they are not all blue?

A. 5/7 B. 23/24 C. 6/7 D. 34/35 E. 8/13

so should we work like this : probability of all blue 3/7*2/6*1/6=1/35 none blue : 1-(1/35)= 34/35

we should be clear of the wordings , shouldn't we ?

Re: A certain deck of cards contains 2 blue cards, 2 red cards [#permalink]
07 May 2012, 15:43

3

This post received KUDOS

Joy111 wrote:

A certain deck of cards contains 2 blue cards, 2 red cards, 2 yellow cards, and 2 green cards. If two cards are randomly drawn from the deck, what is the probability that they will both be not blue?

A. 15/28 B. 1/4 C. 9/16 D. 1/32 E. 1/16

Hi I have a confusion as to how to solve this question , if somebody can help me ?

hello

I have computed the probability for both Cards to be blue and substract one hence total card to 8 probability for the first card 2/8 OR 1/4 For the second 1/7 HENCE 1/28 FOR CARDS

Re: A certain deck of cards contains 2 blue cards, 2 red cards [#permalink]
07 May 2012, 17:59

keiraria wrote:

Joy111 wrote:

A certain deck of cards contains 2 blue cards, 2 red cards, 2 yellow cards, and 2 green cards. If two cards are randomly drawn from the deck, what is the probability that they will both be not blue?

A. 15/28 B. 1/4 C. 9/16 D. 1/32 E. 1/16

Hi I have a confusion as to how to solve this question , if somebody can help me ?

hello

I have computed the probability for both Cards to be blue and substract one hence total card to 8 probability for the first card 2/8 OR 1/4 For the second 1/7 HENCE 1/28 FOR CARDS

1-1/28 = 27/28

HOPE this helps best regards

@keiraria

Thanks for your help but can you solve this one for me too, its same as above only the language has been changed , its NONE now .

If it states that both are not blue then one can be blue , try this one below.

A certain deck of cards contains 2 blue cards, 2 red cards, 2 yellow cards, and 2 green cards. If two cards are randomly drawn from the deck, what is the probability that NONE are blue?

Re: A certain deck of cards contains 2 blue cards, 2 red cards [#permalink]
11 May 2012, 17:41

2

This post received KUDOS

Joy111 wrote:

keiraria wrote:

Joy111 wrote:

A certain deck of cards contains 2 blue cards, 2 red cards, 2 yellow cards, and 2 green cards. If two cards are randomly drawn from the deck, what is the probability that they will both be not blue?

A. 15/28 B. 1/4 C. 9/16 D. 1/32 E. 1/16

Hi I have a confusion as to how to solve this question , if somebody can help me ?

hello

I have computed the probability for both Cards to be blue and substract one hence total card to 8 probability for the first card 2/8 OR 1/4 For the second 1/7 HENCE 1/28 FOR CARDS

1-1/28 = 27/28

HOPE this helps best regards

@keiraria

Thanks for your help but can you solve this one for me too, its same as above only the language has been changed , its NONE now .

If it states that both are not blue then one can be blue , try this one below.

A certain deck of cards contains 2 blue cards, 2 red cards, 2 yellow cards, and 2 green cards. If two cards are randomly drawn from the deck, what is the probability that NONE are blue?

hello Joy thanks for asking me . in fact the way the question is asked has double meaning and it is a little ambigious it is noone are blue it is what I have done :27/28

but if it is that both can not be blue that is the probability to have noNE blue + the probablity to have maximum one blue and hence one of any other colors

Re: A certain deck of cards contains 2 blue cards, 2 red cards [#permalink]
11 May 2012, 22:53

1

This post received KUDOS

@ keira

Thanks for your help but can you solve this one for me too, its same as above only the language has been changed , its NONE now .

If it states that both are not blue then one can be blue , try this one below.

A certain deck of cards contains 2 blue cards, 2 red cards, 2 yellow cards, and 2 green cards. If two cards are randomly drawn from the deck, what is the probability that NONE are blue?[/quote]

hello Joy thanks for asking me . in fact the way the question is asked has double meaning and it is a little ambigious it is noone are blue it is what I have done :27/28

but if it is that both can not be blue that is the probability to have noNE blue + the probablity to have maximum one blue and hence one of any other colors

hence or case

27/28+ 2/8x6/7

Hope it is right and make sense to you

best regards[/quote]

I quess the these two questions should clear the concept

1)Seven beads are in a bag: three blue, two red, and two green. If three beads are randomly drawn from the bag, what is the probability that NONE of them are blue?

answer: (4/7) x (3/6) x (2/5) = 4/35

2)Seven beads are in a bag: three blue, two red, and two green. If three beads are randomly drawn from the bag, what is the probability that they are not all blue?

A. 5/7 B. 23/24 C. 6/7 D. 34/35 E. 8/13

so should we work like this : probability of all blue 3/7*2/6*1/6=1/35 none blue : 1-(1/35)= 34/35

Re: A certain deck of cards contains 2 blue cards, 2 red cards [#permalink]
20 Oct 2012, 21:01

Joy111 wrote:

A certain deck of cards contains 2 blue cards, 2 red cards, 2 yellow cards, and 2 green cards. If two cards are randomly drawn from the deck, what is the probability that they will both be not blue?

A. 15/28 B. 1/4 C. 9/16 D. 1/32 E. 1/16

Hi I have a confusion as to how to solve this question , if somebody can help me ?

The question asks " they will both be not blue". Considering that these are draws without replacement there are following possibilities : draw 1, draw 2 ===== ===== 1) Not Blue, Blue; 2) Blue, Not Blue; 3) Blue, Blue; 4) Not Blue, not Blue;

The answer has to be either P(4) OR all exclusion of the 3 previous conditions i.e. 1- [P(1) + P(2) + P(3)] => neither of the draws are blue