Last visit was: 24 Apr 2026, 12:07 It is currently 24 Apr 2026, 12:07
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
Mugdho
Joined: 27 Feb 2019
Last visit: 11 Nov 2023
Posts: 93
Own Kudos:
250
 [7]
Given Kudos: 495
Posts: 93
Kudos: 250
 [7]
1
Kudos
Add Kudos
6
Bookmarks
Bookmark this Post
User avatar
yashikaaggarwal
User avatar
Senior Moderator - Masters Forum
Joined: 19 Jan 2020
Last visit: 29 Mar 2026
Posts: 3,089
Own Kudos:
3,158
 [3]
Given Kudos: 1,510
Location: India
GPA: 4
WE:Analyst (Internet and New Media)
Posts: 3,089
Kudos: 3,158
 [3]
2
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
User avatar
Mugdho
Joined: 27 Feb 2019
Last visit: 11 Nov 2023
Posts: 93
Own Kudos:
Given Kudos: 495
Posts: 93
Kudos: 250
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 24 Apr 2026
Posts: 11,229
Own Kudos:
Given Kudos: 335
Status:Math and DI Expert
Location: India
Concentration: Human Resources, General Management
GMAT Focus 1: 735 Q90 V89 DI81
Products:
Expert
Expert reply
GMAT Focus 1: 735 Q90 V89 DI81
Posts: 11,229
Kudos: 45,008
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Mugdho
How many 4 digit numbers exist where digits are in ascending order and how many 4 digit numbers exist where digits are in descending order?

a) 1620 and 1160
b) 1080 and 1024
c) 960 and 737
d) 1080 and 1260
e) 1440 and 1230


I have doubt about the official answer. Can anyone clarify this ?

Posted from my mobile device


Not a GMAT-type question.

If it were GMAT, it will ask you the ways where we talk of different digits.
The answer in descending order will be 10C4 or 210, that is ways to select 4 digits out of 10 digits.


But even if the question here means that there could be repetition, that is 3221 is also to be considered, the total may not be correct. Let us get the maximum possible answer to it
1) All 4 digits different - 10C4 = 210
2) 3 different digits with one used twice - 10C3 for choosing 3 digits and 3 for any of the three being used twice as the similar digits have to be placed together - 10C3*3 = 120*3 = 360
3) 2 different digits with both used twice - 10C2 for choosing 2 digits and only one possibility as the similar digits have to be placed together - 10C2 = 45...Example - 2211 or 4411 etc
4) 2 different digits with one used thrice - 10C2 for choosing 2 digits and both the digits can be used thrice - 10C2*2 = 90...Example - 2111 or 2221 etc
Total - 210+360+45+90 = 715
5) All digits same, so 9 such ways could be added at the best so 715+9 = 724

This is what comes to my mind when I look at the question. I don't know if I am missing something, but the answer does not seem to be correct under any circumstances.
User avatar
Kushchokhani
Joined: 05 Jan 2020
Last visit: 03 Apr 2024
Posts: 508
Own Kudos:
654
 [1]
Given Kudos: 692
Status:Admitted to IIM Shillong (PGPEx 2023-24)
Affiliations: CFA Institute; ICAI; BCAS
Location: India
WE 2: EA to CFO (Consumer Products)
GPA: 3.78
WE:Corporate Finance (Commercial Banking)
Products:
Posts: 508
Kudos: 654
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
yashikaaggarwal
So the combination of numbers will be a factor of 10 and will have fewer numbers than those of ascending as the ascending series smallest number is 1234, which goes up to 9999 and descending order series is already 3000 numbers short of the 1000-9999 series.

yashikaaggarwal

ascending series goes up to 6789 or 9999? If the answer is up to 6789, then your rationale that ascending series will have more numbers than descending series is weakened.
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,975
Own Kudos:
Posts: 38,975
Kudos: 1,117
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Math Expert
109818 posts
Tuck School Moderator
853 posts