Last visit was: 26 Apr 2026, 08:20 It is currently 26 Apr 2026, 08:20
Home
Messages
Tests
Schools
Events
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
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 26 Apr 2026
Posts: 109,837
Own Kudos:
811,391
 [15]
Given Kudos: 105,896
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: 109,837
Kudos: 811,391
 [15]
If x = 2^b - (8^8 + 8^6), for which of the following b values is x clo 02 Jul 2021, 08:45
1
Kudos
Add Kudos
14
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:

45% (medium)

Question Stats:

66% (01:47) correct 34% (02:07) wrong based on 628 sessions

History

Date
Time
Result
Not Attempted Yet
If \(x = 2^b - (8^8 + 8^6)\), for which of the following b values is x closest to zero?

(A) 20
(B) 24
(C) 25
(D) 30
(E) 42
ShowHide Answer
Official Answer
B
User avatar
Kinshook
User avatar
Major Poster
Joined: 03 Jun 2019
Last visit: 26 Apr 2026
Posts: 5,987
Own Kudos:
5,860
 [2]
Given Kudos: 163
Location: India
Schools: HBS '26 CBS '26 Wharton '26
GMAT 1: 690 Q50 V34
WE:Engineering (Transportation)
Products:
My Reviews
Schools: HBS '26 CBS '26 Wharton '26
GMAT 1: 690 Q50 V34
Posts: 5,987
Kudos: 5,860
 [2]
If x = 2^b - (8^8 + 8^6), for which of the following b values is x clo 02 Jul 2021, 08:59
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Asked: If \(x = 2^b - (8^8 + 8^6)\), for which of the following b values is x closest to zero?

\(x = 2^b - 8^6(8^2 + 1) ~ 2^b - 2^18*2^6 ~ 2^b - 2^24\)
For b=24, x is closest to 0.

IMO B
User avatar
Showmeyaa
User avatar
Joined: 24 Jun 2019
Last visit: 08 Sep 2023
Posts: 427
Own Kudos:
528
 [3]
Given Kudos: 117
Location: India
Concentration: Marketing, Strategy
Products:
My Reviews
Posts: 427
Kudos: 528
 [3]
If x = 2^b - (8^8 + 8^6), for which of the following b values is x clo 02 Jul 2021, 14:46
3
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
If \(x = 2^b - (8^8 + 8^6)\), for which of the following b values is x closest to zero?

(A) 20
(B) 24
(C) 25
(D) 30
(E) 42
Show more

\(x = 2^b - (8^8 + 8^6)\)
\(x = 2^b - 8^6(8^2 + 1)\)
\(x = 2^b - 2^{3*6}(65)\)
\(x = 2^b - 2^{18}(65)\)
\(x = 2^b - 2^{18}* 2^6\) (As, 65 ~ 2^6 + 1)
\(x = 2^b - 2^{24}\)
So, (B) IMO!
avatar
LerPrivet
avatar
Joined: 18 Jul 2021
Last visit: 12 Feb 2022
Posts: 1
Posts: 1
Kudos: 0
If x = 2^b - (8^8 + 8^6), for which of the following b values is x clo 10 Aug 2021, 23:47
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Could smb please explain, why we write 2^b-2^18(2^6+1) instead of 2^b-2^24-2^18?

Isn't it 8^8=(2^3)^8 = 8^24 and so on?

Thnx
User avatar
Showmeyaa
User avatar
Joined: 24 Jun 2019
Last visit: 08 Sep 2023
Posts: 427
Own Kudos:
528
Given Kudos: 117
Location: India
Concentration: Marketing, Strategy
Products:
My Reviews
Posts: 427
Kudos: 528
If x = 2^b - (8^8 + 8^6), for which of the following b values is x clo 13 Aug 2021, 23:09
Kudos
Add Kudos
Bookmarks
Bookmark this Post
LerPrivet
Could smb please explain, why we write 2^b-2^18(2^6+1) instead of 2^b-2^24-2^18?

Isn't it 8^8=(2^3)^8 = 8^24 and so on?

Thnx
Show more

If I understood your question correctly, you want to understand why the question stem was broken down to 2^b-2^18(2^6+1) instead of 2^b - 2^24 - 2^18
That's because we are interested in finding the value of b which makes the value of x close to 0. Ideally, every base should be 2 so that we can easily find for what value of b would x be closest to zero.

2^b - 2^24 - 2^18 -> This form doesn't help explain what could be possible value of b whereas this form(2^b-2^18(2^6+1)) helps.

Let me know, in case you had a different question in mind!
User avatar
Malar95
User avatar
Joined: 29 Oct 2023
Last visit: 13 Jun 2024
Posts: 328
Own Kudos:
168
Given Kudos: 11
Location: Malaysia
Posts: 328
Kudos: 168
If x = 2^b - (8^8 + 8^6), for which of the following b values is x clo 26 Dec 2023, 03:48
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I was just having fun with numbers and then I looked at the answer option and tadaaa, answer was there. Hope that helped. Hope its correct.
Was doing it directly from the book.
Attachments

File comment: My answer
Image 2 for Q explanation.jpg
Image 2 for Q explanation.jpg [ 18.94 KiB | Viewed 3177 times ]

User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,988
Own Kudos:
1,118
Posts: 38,988
Kudos: 1,118
If x = 2^b - (8^8 + 8^6), for which of the following b values is x clo 16 Mar 2025, 08:54
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:
Bunuel
Math Expert
109837 posts
Krunaal
Tuck School Moderator
852 posts