Last visit was: 10 Jul 2025, 12:29 It is currently 10 Jul 2025, 12:29
Home
GMAT
Messages
Tests
Schools
Events
Rewards
Chat
My Profile
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
   1   2 
705-805 Level|   Probability|      
User avatar
tann412
User avatar
Joined: 09 Apr 2018
Last visit: 06 Dec 2022
Posts: 16
Own Kudos:
20
 [5]
Given Kudos: 35
Posts: 16
Kudos: 20
 [5]
If the probability that Stock A will increase in value during the next 16 Sep 2018, 09:47
3
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
Using Venn Diagrams is also a great way to solve such a question.
Attachments

File comment: Stock A Stock B Venn
Probability - Stock A Stock B.jpg
Probability - Stock A Stock B.jpg [ 39.89 KiB | Viewed 6438 times ]

User avatar
mmdfl
User avatar
Joined: 06 Aug 2022
Last visit: 13 Dec 2024
Posts: 108
Own Kudos:
218
 [1]
Given Kudos: 165
Location: Brazil
Concentration: Technology, Economics
Posts: 108
Kudos: 218
 [1]
If the probability that Stock A will increase in value during the next 24 Jun 2023, 18:11
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
i illustrated what was said in the previous answers to more visual folks like me
Attachments

il.png
il.png [ 729.82 KiB | Viewed 1481 times ]

User avatar
007saisurya
User avatar
Joined: 28 Jan 2023
Last visit: 01 May 2024
Posts: 8
Own Kudos:
11
Given Kudos: 4
Location: India
Concentration: Finance, Economics
Schools: ISB '27 NUS '26
GPA: 4
Schools: ISB '27 NUS '26
Posts: 8
Kudos: 11
If the probability that Stock A will increase in value during the next 11 Jul 2023, 19:51
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Answers have been complicated
a happening - .54
a not happening - .46
b happening - .68
b not happening - .32
for A not happening and B not happening to be max - find the lowest of the not happenings - 0.32
User avatar
sachi-in
User avatar
Joined: 12 Oct 2023
Last visit: 03 Mar 2025
Posts: 125
Own Kudos:
234
Given Kudos: 146
Posts: 125
Kudos: 234
If the probability that Stock A will increase in value during the next 24 Jan 2024, 10:14
Kudos
Add Kudos
Bookmarks
Bookmark this Post
MHIKER
If the probability that Stock A will increase in value during the next month is 0.54, and the probability that Stock B will increase in value during the next month is 0.68. What is the greatest value for the probability that neither of these two events will occur?

A. 0.22
B. 0.32
C. 0.37
D. 0.46
E. 0.63

Show Spoiler
Attachment:
2017-09-08.png


This problem can be reduced to an problem in Set making it super easy to solve.

Imagine there are 100 datasets (A, B) A is true or false depending on wheather there is a increase in A ( same for B )

there will be 54 such As with true
there will be 68 usch Bs with true

Union of A U B is set of all pairs ( A, B ) where there is a rise in both stocks.

Similarly where there is no rise = Whole Set - (Rise in A) - (Rise in B) + (Rise in both A and B)

This is maximum when the (Rise in both A and B) = (Rise in A)
User avatar
Rebaz
User avatar
Joined: 14 Feb 2014
Last visit: 08 Jul 2025
Posts: 133
Own Kudos:
31
Given Kudos: 4,739
Products:
GMAT Club Tests
Posts: 133
Kudos: 31
If the probability that Stock A will increase in value during the next 19 May 2024, 03:48
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Raihanuddin
Please check the attachment
­Finally i understand this question by vissualizing it this way instead of all those long posts(which i appreciate as well).

Thank you a lot!
User avatar
findingmyself
User avatar
Joined: 06 Apr 2025
Last visit: 09 Jul 2025
Posts: 88
Own Kudos:
11
Given Kudos: 37
Posts: 88
Kudos: 11
If the probability that Stock A will increase in value during the next 13 Apr 2025, 06:19
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hi All,

Another approach I have figured out for this question. Pl comment if my thought process is correct

P(A or B)= P(A)+(PB)-P(A and B)+ P(Neither)
What we want to find out is MAX value of P(neither)

P(A or B)=1
1=0.54+0.68-Both+Neither
1-0.54-0.68+Both= Neither
For Neither to be Highest, Both has to be equal to the lowest possible probability of A/B, In this case 0.54
Substituting 0.54 in the above, we get 1-0.54-0.68+0.54= 1-0.68= 0.32-->32%


MHIKER
If the probability that Stock A will increase in value during the next month is 0.54, and the probability that Stock B will increase in value during the next month is 0.68. What is the greatest value for the probability that neither of these two events will occur?

A. 0.22
B. 0.32
C. 0.37
D. 0.46
E. 0.63

Show Spoiler
Attachment:
2017-09-08.png
User avatar
kanwar08
User avatar
Joined: 18 Apr 2023
Last visit: 10 Jul 2025
Posts: 18
Own Kudos:
2
Given Kudos: 42
Location: India
Schools: ISB '26
GMAT 1: 580 Q47 V26
Products:
GMAT Club Tests
Schools: ISB '26
GMAT 1: 580 Q47 V26
Posts: 18
Kudos: 2
If the probability that Stock A will increase in value during the next 30 Jun 2025, 20:47
Kudos
Add Kudos
Bookmarks
Bookmark this Post
This problem can be easily addressed via the Ven Diagram.

Draw two Ven Diagram for A and B. Now, my goal is to maximise the neither, which is only possible when the sets have total overlap on each other.

So, max of either will be 0.68. So, the max neither set will be 1 - 0.68 = 0.32
User avatar
RoopalKaushal
User avatar
Joined: 05 Dec 2022
Last visit: 09 Jul 2025
Posts: 2
Given Kudos: 26
Location: India
Posts: 2
Kudos: 0
If the probability that Stock A will increase in value during the next 02 Jul 2025, 03:58
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Not A = 1- 0.54 = 0.46
Not B = 1-0.68 = 0.32
Highest common probability among both = 0.32
   1   2 
Moderators:
Bunuel
Math Expert
102624 posts
Krunaal
PS Forum Moderator
685 posts