Find all School-related info fast with the new School-Specific MBA Forum

It is currently 27 Jul 2016, 07:47
GMAT Club Tests

Close

GMAT Club Daily Prep

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

What is the probability that it will rain on each of the

  post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Current Student
User avatar
Joined: 29 Jan 2005
Posts: 5239
Followers: 23

Kudos [?]: 301 [0], given: 0

What is the probability that it will rain on each of the [#permalink]

Show Tags

New post 23 Nov 2005, 07:44
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

50% (01:01) correct 50% (00:00) wrong based on 25 sessions

HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

What is the probability that it will rain on each of the next 3 days if the probability of rain on any single day is the same in that period?

1. The probability of no rain throughout the fist two days is 36%
2. The probability of rain on the 3rd day is 40%
Manager
Manager
avatar
Joined: 15 Aug 2005
Posts: 136
Followers: 2

Kudos [?]: 21 [0], given: 0

Re: DS PGMAT (probability of rain) [#permalink]

Show Tags

New post 23 Nov 2005, 07:51
GMATT73 wrote:
What is the probability that it will rain on each of the next 3 days if the probability of rain on any single day is the same in that period?

1. The probability of no rain throughout the fist two days is 36%
2. The probability of rain on the 3rd day is 40%



I would go with D

1. lets say the prob it does not rains on a day is - 1/x
then 1/(x^2) =36/100. so we can sove for x and find the prob it rains on a day (1 - 1/x)---> sufficient

2. Since the prob is same one each of the 3 days we can find the prob that it rains on each of the next 3 days ---> sufficient
VP
VP
avatar
Joined: 30 Sep 2004
Posts: 1488
Location: Germany
Followers: 6

Kudos [?]: 251 [0], given: 0

 [#permalink]

Show Tags

New post 23 Nov 2005, 08:09
B)...1) is out b/c 36% is the prob for no rain and 64% ist the prob for at least 1 rainy day. so we cannot calc the prob for 2 days of rain. => insuff
2) is ok
_________________

If your mind can conceive it and your heart can believe it, have faith that you can achieve it.

Current Student
User avatar
Joined: 29 Jan 2005
Posts: 5239
Followers: 23

Kudos [?]: 301 [0], given: 0

 [#permalink]

Show Tags

New post 23 Nov 2005, 22:01
Good work believe. This is an upper bin problem and the OA is D.
VP
VP
avatar
Joined: 06 Jun 2004
Posts: 1059
Location: CA
Followers: 2

Kudos [?]: 105 [0], given: 0

 [#permalink]

Show Tags

New post 23 Nov 2005, 22:13
Matt, could you post the OE? Thanks
1 KUDOS received
VP
VP
avatar
Joined: 30 Sep 2004
Posts: 1488
Location: Germany
Followers: 6

Kudos [?]: 251 [1] , given: 0

 [#permalink]

Show Tags

New post 24 Nov 2005, 01:19
1
This post received
KUDOS
christoph wrote:
B)...1) is out b/c 36% is the prob for no rain and 64% ist the prob for at least 1 rainy day. so we cannot calc the prob for 2 days of rain. => insuff
2) is ok


D)...

1) 36% when its no rain on both days => 6/10 prob that its not raining on 1 day and 4/10 prob that its raining. so (6/10)^3 thats its raining on exactly 3 days. => suff

2) suff
_________________

If your mind can conceive it and your heart can believe it, have faith that you can achieve it.

SVP
SVP
User avatar
Joined: 05 Apr 2005
Posts: 1731
Followers: 5

Kudos [?]: 60 [0], given: 0

 [#permalink]

Show Tags

New post 24 Nov 2005, 01:26
TeHCM wrote:
Matt, could you post the OE? Thanks
from i, the prob that it will rain on ach of first and second day is = prob (rain on 1st day) prob (rain on 2nd day) = sqrt(0.36) = 0.4 or 40%. suff.

from ii, if the prob that it rains on third day is 40%, the prob of raining on 1st and 2nd day is also 40%. suff.
SVP
SVP
User avatar
Joined: 28 May 2005
Posts: 1723
Location: Dhaka
Followers: 7

Kudos [?]: 218 [0], given: 0

 [#permalink]

Show Tags

New post 24 Nov 2005, 04:47
1
This post was
BOOKMARKED
i did it in a different way.

it is a binomial distribution.

so let probability of rain on any single day is x and probability of not rainint is 1-x.

so from statement 1
we get, The probability of no rain throughout the fist two days is 36%
that means nP0 = (1-x)^2 = .36
so, 1-x = .6 so x = .4

therefore probability that it will rain on each of the next 3 days = x^3= .4^3 = .064
so it is suff...

from statement 2) we get The probability of rain on the 3rd day is 40%
that means 3c1 * x. ((1-x)^2 = .4

or, x. (1-x) ^2= .4/3
we can solve for x from here as well and find what is x^3.
so this one is also suff....

Hence, D is the answer.
_________________

hey ya......

Senior Manager
Senior Manager
User avatar
Joined: 15 Apr 2005
Posts: 417
Location: India, Chennai
Followers: 2

Kudos [?]: 13 [0], given: 0

Re: DS PGMAT (probability of rain) [#permalink]

Show Tags

New post 24 Nov 2005, 04:55
GMATT73 wrote:
What is the probability that it will rain on each of the next 3 days if the probability of rain on any single day is the same in that period?

1. The probability of no rain throughout the fist two days is 36%
2. The probability of rain on the 3rd day is 40%


I agree its D. My working is same as many others here.
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 10613
Followers: 495

Kudos [?]: 129 [0], given: 0

Premium Member
Re: What is the probability that it will rain on each of the [#permalink]

Show Tags

New post 28 Feb 2016, 11:19
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Re: What is the probability that it will rain on each of the   [#permalink] 28 Feb 2016, 11:19
Display posts from previous: Sort by

What is the probability that it will rain on each of the

  post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.