Last visit was: 19 Nov 2025, 08:01 It is currently 19 Nov 2025, 08:01
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
805+ Level|   Word Problems|      
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 19 Nov 2025
Posts: 105,389
Own Kudos:
778,260
 [18]
Given Kudos: 99,977
Products:
GMAT Club Tests Forum Quiz
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 105,389
Kudos: 778,260
 [18]
Some people form a joint account for one year with the condition that 07 Nov 2019, 01:44
1
Kudos
Add Kudos
17
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

95% (hard)

Question Stats:

58% (03:14) correct 42% (03:15) wrong based on 173 sessions

History

Date
Time
Result
Not Attempted Yet
Some people form a joint account for one year with the condition that every month each member deposits an amount equal to the number of members in the account in that month. Also, the person who withdraws from the account before the end of the year get his/her amount at the end of the year. After 6 months, 1/4th of the people withdraw and 1/3rd of the remaining withdraw after 3 months. At the end of the year there is an amount of Rs. 4860 in the account before paying of the withdrawn amounts. Find out the number of people in the beginning of the year.

A. 12
B. 24
C. 36
D. 48
E. 60


Are You Up For the Challenge: 700 Level Questions
ShowHide Answer
Official Answer
B
Most Helpful Reply
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 15 Nov 2025
Posts: 11,238
Own Kudos:
43,703
 [4]
Given Kudos: 335
Status:Math and DI Expert
Location: India
Concentration: Human Resources, General Management
GMAT Focus 1: 735 Q90 V89 DI81
Products:
My Reviews
Expert
Expert reply
GMAT Focus 1: 735 Q90 V89 DI81
Posts: 11,238
Kudos: 43,703
 [4]
Some people form a joint account for one year with the condition that 07 Nov 2019, 20:59
4
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
Some people form a joint account for one year with the condition that every month each member deposits an amount equal to the number of members in the account in that month. Also, the person who withdraws from the account before the end of the year get his/her amount at the end of the year. After 6 months, 1/4th of the people withdraw and 1/3rd of the remaining withdraw after 3 months. At the end of the year there is an amount of Rs. 4860 in the account before paying of the withdrawn amounts. Find out the number of people in the beginning of the year.

A. 12
B. 24
C. 36
D. 48
E. 60


Are You Up For the Challenge: 700 Level Questions
Show more

Let there be x members in the beginning..
So the duration can be divided in 3 parts..
(I) First 6 months -- number is x, so money per month = x*x, and for 6 months = \(6*x^2\)
(II) Next 3 months -- number reduces to \(\frac{3x}{4}\), so money per month = \((\frac{3x}{4})^2\), and for 3 months = \(3*(\frac{3x}{4})^2=\frac{27x^2}{16}\)
(III) Last 3 months -- number reduces to \(\frac{3x}{4}*\frac{2}{3}=\frac{x}{2}\), so money per month = \((\frac{x}{2})^2\), and for 3 months = \(3*(\frac{x}{2})^2=\frac{3x^2}{4}\)

Total = \(6x^2+\frac{27x^2}{16}+\frac{3x^2}{4}=4860........\frac{135x^2}{16}=4860........x^2=4860*\frac{16}{135}=36*16.....x=6*4=24\)

B
General Discussion
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 15 Nov 2025
Posts: 11,238
Own Kudos:
43,703
Given Kudos: 335
Status:Math and DI Expert
Location: India
Concentration: Human Resources, General Management
GMAT Focus 1: 735 Q90 V89 DI81
Products:
My Reviews
Expert
Expert reply
GMAT Focus 1: 735 Q90 V89 DI81
Posts: 11,238
Kudos: 43,703
Some people form a joint account for one year with the condition that 07 Nov 2019, 21:07
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
Some people form a joint account for one year with the condition that every month each member deposits an amount equal to the number of members in the account in that month. Also, the person who withdraws from the account before the end of the year get his/her amount at the end of the year. After 6 months, 1/4th of the people withdraw and 1/3rd of the remaining withdraw after 3 months. At the end of the year there is an amount of Rs. 4860 in the account before paying of the withdrawn amounts. Find out the number of people in the beginning of the year.

A. 12
B. 24
C. 36
D. 48
E. 60


Are You Up For the Challenge: 700 Level Questions
Show more

You can also make use of choices..

A. 12...
First 6 months = \(6*12*12\).... next 3 months=\(3*(12*\frac{3}{4})^2=3*9*9\)...last 3 months = \(3*(9*\frac{2}{3})^2=3*6*6\)..
Total = \(864+243+108=1215\neq{4860}\)

B. 24...
First 6 months = \(6*24*24\).... next 3 months=\(3*(24*\frac{3}{4})^2=3*18*18\)...last 3 months = \(3*(18*\frac{2}{3})^2=3*12*12\)..
Total = \(4860\)..
Also a quick look at choice A .. A is 12 and B is 2 times and we are dealing with x^2 only and in each term, so our answer here will be (2x)^2= 4* value for x = 4*1215=4860

No need to go furhter

B
User avatar
catinabox
User avatar
Joined: 27 Nov 2019
Last visit: 18 Nov 2025
Posts: 567
Own Kudos:
588
Given Kudos: 223
Location: United States (IL)
Schools: Kellogg '24 (M)
GMAT 1: 770 Q50 V44
GPA: 4
Products:
GMAT Club Tests
Schools: Kellogg '24 (M)
GMAT 1: 770 Q50 V44
Posts: 567
Kudos: 588
Some people form a joint account for one year with the condition that 27 Jul 2020, 04:28
Kudos
Add Kudos
Bookmarks
Bookmark this Post
This question is excellent, however, you might want to rephrase this line:

"Also, the person who withdraws from the account before the end of the year get his/her amount at the end of the year."

The wording is causing some confusion.
User avatar
EgmatQuantExpert
User avatar
e-GMAT Representative
Joined: 04 Jan 2015
Last visit: 02 Apr 2024
Posts: 3,663
Own Kudos:
20,165
Given Kudos: 165
Expert
Expert reply
Posts: 3,663
Kudos: 20,165
Some people form a joint account for one year with the condition that 27 Jul 2020, 05:14
Kudos
Add Kudos
Bookmarks
Bookmark this Post

Solution


Given

    • Every month each member deposits an amount equal to the number of members in the account in that month
    • The person who withdraws from the account before the end of the year gets his/her amount at the end of the year.
    • After 6 months, 1/4th of the people withdraw and 1/3rd of the remaining withdraw after 3 months.
    • Of the monsters who can spit fireballs, 8 also blow freezing wind.
    • At the end of the year, there is an amount of Rs. 4860 in the account before paying off the withdrawn amounts.

To Find

• Number of members in the beginning.

Approach and Working Out

    • After 6 months \(\frac{1}{4}\)th leaves.
      o Remaining = \(\frac{3}{4}\)th.
    • After another 3 months \(\frac{1}{3}\)th of \(\frac{3}{4}\)th left.
      o This is \(\frac{1}{4}\)th of the total.
      o Remaining = 1 – \(\frac{1}{4}\) – \(\frac{1}{4}\)= \(\frac{1}{2}\)
    • From this I can see the answer is a multiple of 4.
    • Let me take the number to be 4x.
      o 6 months = 6 × \((4x)^2\)
        = \(96x^2\)
      o Next 3 months = 3× \((3x)^2\)
        = \(27x^2\)
      o End 3 months = 3 × (2x)^2.
        = \(12x^2\)
    • Total amount = 96\(x^2\) + 27\(x^2\) + 12\(x^2\) = 4860
      Or, 135\(x^2\) = 4860
      Or, \(x^2\) = 36
      Or, x = 6
    • Answer = 4x = 24

Correct Answer: Option B
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,588
Own Kudos:
1,079
Posts: 38,588
Kudos: 1,079
Some people form a joint account for one year with the condition that 16 Jun 2024, 14:24
Kudos
Add Kudos
Bookmarks
Bookmark this Post
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.
Moderators:
Bunuel
Math Expert
105389 posts
Krunaal
Tuck School Moderator
805 posts