Last visit was: 10 Jul 2025, 12:51 It is currently 10 Jul 2025, 12:51
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.
Close
Request Expert Reply
Confirm Cancel
User avatar
agdimple333
Joined: 24 Mar 2011
Last visit: 13 Aug 2013
Posts: 226
Own Kudos:
785
 [86]
Given Kudos: 20
Location: Texas
Posts: 226
Kudos: 785
 [86]
8
Kudos
Add Kudos
77
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 10 July 2025
Posts: 102,624
Own Kudos:
Given Kudos: 98,170
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 102,624
Kudos: 740,159
 [22]
6
Kudos
Add Kudos
16
Bookmarks
Bookmark this Post
User avatar
akshayk
Joined: 06 Jul 2016
Last visit: 21 Sep 2020
Posts: 273
Own Kudos:
402
 [9]
Given Kudos: 99
Location: Singapore
Concentration: Strategy, Finance
Posts: 273
Kudos: 402
 [9]
6
Kudos
Add Kudos
3
Bookmarks
Bookmark this Post
General Discussion
User avatar
srcc25anu
Joined: 11 Jun 2010
Last visit: 14 Aug 2014
Posts: 35
Own Kudos:
91
 [1]
Given Kudos: 17
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
WE can do this without even framing eqn.

Stat 1 says that avg of all shirts and sweaters = 21.00$ means its closer to the price of sweaters ($25) vis-a-vis that of shirts ($20) hence more of sweaters must have been sold.

hence statement 1 alone is sufficient to answer the question

stat 2 says that 15 shirts + 25 sweaters = 420 hence cannot be solved.

thus Ans - A
User avatar
amit2k9
Joined: 08 May 2009
Last visit: 18 Jun 2017
Posts: 538
Own Kudos:
Given Kudos: 10
Status:There is always something new !!
Affiliations: PMI,QAI Global,eXampleCG
Posts: 538
Kudos: 623
Kudos
Add Kudos
Bookmarks
Bookmark this Post
15 sh + 25 sw = 21(sh+sw)
4sw = 6sh
2sw = 3sh Sufficient.

15 sh + 25 sw = 420
3sh + 5sw = 84

5 * 16 = 80 (max sw = 16)
Hence by trial method sw = 15, sh = 3

3* 28 = 84 (max sh = 28)
hence by trial method 3*sh = 54 gives sw = 6
meaning sh = 18,sw = 6. Hence not sufficient.

Thus A.
avatar
dchow23
Joined: 16 May 2011
Last visit: 18 Feb 2013
Posts: 51
Own Kudos:
Given Kudos: 2
Posts: 51
Kudos: 46
Kudos
Add Kudos
Bookmarks
Bookmark this Post
from statement 2,

shirts x
sweaters y

15x +20y = 420

Can we say that since 60 is a common multiple between the 15 and 20, there will be more than one answer that can satisfy the equation?
If there is a common multiple for
User avatar
JeffTargetTestPrep
User avatar
Target Test Prep Representative
Joined: 04 Mar 2011
Last visit: 05 Jan 2024
Posts: 2,996
Own Kudos:
Given Kudos: 1,646
Status:Head GMAT Instructor
Affiliations: Target Test Prep
Expert
Expert reply
Posts: 2,996
Kudos: 7,922
Kudos
Add Kudos
Bookmarks
Bookmark this Post
agdimple333
During a sale, a clothing store sold each shirt at a price of $15 and each sweater at a price of $25.00 Did the store sell more sweaters than shirts during the sale?

1) The average of the prices of all of the shirts and sweaters that the store sold during the sale was $21.00
2) The total of the prices of all of the shirts and sweaters that the store sold during the sale was $420.00

The average of the prices of all of the shirts and sweaters that the store sold during the sale was $21.00.

Since the average price of $21 is closer to $25 than it is to $15, there must be more sweaters sold than shirts. Statement one alone is sufficient.

Statement Two Alone:

The total of the prices of all of the shirts and sweaters that the store sold during the sale was $420.00.

It’s possible that 12 sweaters and 8 shirts are sold since 12 x 25 + 8 x 15 = 300 + 120 = $420. It’s also possible that 6 sweaters and 18 shirts are sold since 6 x 25 + 18 x 15 = 150 + 270 = $420. In the former example, more sweaters were sold; however, in the latter example, more shirts were sold. Statement two alone is not sufficient.

Answer: A
User avatar
Hovkial
Joined: 23 Apr 2019
Last visit: 24 Nov 2022
Posts: 803
Own Kudos:
Given Kudos: 202
Status:PhD trained. Education research, management.
Posts: 803
Kudos: 2,291
Kudos
Add Kudos
Bookmarks
Bookmark this Post
The following solution uses the method of algebraic manipulation. This alternative method is longer, but can provide certainty.

Let the number of shirts sold be H and the number of sweaters sold be W.

1) The average of the prices of all of the shirts and sweaters that the store sold during the sale was $21.00

Average of the prices = (Total price of H shirts and W sweaters)/(Total number of shirts and sweaters).

(15H + 25W)/(H + W) = 21
W/H = 3/2

This ratio tells us that the number of sweaters sold (a multiple of 3) will always be greater than the number of shirts sold (a multiple of 2). SUFFICIENT

2) The total of the prices of all of the shirts and sweaters that the store sold during the sale was $420.00

15H + 25W = 420
3H + 5W = 84 ............. (a)

We have to determine whether W > H.

Start with W > H ? Algebraically manipulate this inequality to make use of equation (a).

W > H ?
5W > 5H ?
5W + 3H > 8H ?
84 > 8H ?

Is H < 21/2 ?

We arrive at the question: is the number of shirts sold less than 21/2? Since we do not have any information about the number of shirts sold, we cannot answer the original question about whether the number of sweaters sold is greater than the number of shirts sold. INSUFFICIENT

ANSWER: (A)
User avatar
Vineet1102
Joined: 11 Feb 2024
Last visit: 10 Jul 2025
Posts: 13
Own Kudos:
Given Kudos: 16
Posts: 13
Kudos: 1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hi while solving this question, I had the concept of Diophantine-equations in my mind and had seen one post discussing the same
https://gmatclub.com/forum/joanna-bought-only-0-15-stamps-and-0-29-stamps-how-many-0-15-stamp-101743.html

How ever even after verifying acc to Magophon 's method, the statement 2 gives out atleast 5 unique solutions
Can someone explain me how? thanks
@Bunuel
Moderator:
Math Expert
102624 posts