Last visit was: 24 Apr 2026, 10:42 It is currently 24 Apr 2026, 10:42
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
Sub 505 (Easy)|   Exponents|               
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 24 Apr 2026
Posts: 109,814
Own Kudos:
811,036
 [7]
Given Kudos: 105,873
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: 109,814
Kudos: 811,036
 [7]
Which of the following is equal to x^18 for all positive values of x ? 08 Oct 2018, 03:49
3
Kudos
Add Kudos
4
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:

5% (low)

Question Stats:

95% (00:24) correct 5% (00:39) wrong based on 1635 sessions

History

Date
Time
Result
Not Attempted Yet
Which of the following is equal to \(x^{18}\) for all positive values of x ?


A. \(x^9 + x^9\)

B. \((x^2)^9\)

C. \((x^9)^9\)

D. \((x^3)^{15}\)

E. \(\frac{x^4}{x^{22}}\)
ShowHide Answer
Official Answer
B
Need more similar questions? Run a 5 to 10 question quiz in GMAT Club Forum Quiz →
User avatar
Salsanousi
User avatar
Joined: 19 Oct 2013
Last visit: 29 Dec 2020
Posts: 391
Own Kudos:
358
 [2]
Given Kudos: 117
Location: Kuwait
GPA: 3.2
WE:Engineering (Real Estate)
Posts: 391
Kudos: 358
 [2]
Which of the following is equal to x^18 for all positive values of x ? 08 Oct 2018, 04:00
1
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
Bunuel
Which of the following is equal to \(x^{18}\) for all positive values of x ?


A. \(x^9 + x^9\)

B. \((x^2)^9\)

C. \((x^9)^9\)

D. \((x^3)^{15}\)

E. \(\frac{x^4}{x^{22}}\)
Show more

Answer choice B.

\(x^a^b\) = \(x^{a*b}\)

Posted from my mobile device
User avatar
Arpitkumar
User avatar
Joined: 30 May 2018
Last visit: 22 Mar 2021
Posts: 51
Own Kudos:
45
Given Kudos: 121
Concentration: General Management, Marketing
Schools: IIMA PGPX"20 INSEAD Jan '19 HBS '21
GMAT 1: 750 Q49 V45
GPA: 3.45
WE:Other (Retail: E-commerce)
Schools: IIMA PGPX"20 INSEAD Jan '19 HBS '21
GMAT 1: 750 Q49 V45
Posts: 51
Kudos: 45
Which of the following is equal to x^18 for all positive values of x ? 08 Oct 2018, 04:21
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Answer choice B , for all positive values of X
User avatar
KSBGC
User avatar
Joined: 31 Oct 2013
Last visit: 10 Mar 2022
Posts: 1,240
Own Kudos:
1,509
 [1]
Given Kudos: 635
Concentration: Accounting, Finance
GPA: 3.68
WE:Analyst (Accounting)
Posts: 1,240
Kudos: 1,509
 [1]
Which of the following is equal to x^18 for all positive values of x ? 08 Oct 2018, 05:20
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
Which of the following is equal to \(x^{18}\) for all positive values of x ?


A. \(x^9 + x^9\)

B. \((x^2)^9\)

C. \((x^9)^9\)

D. \((x^3)^{15}\)

E. \(\frac{x^4}{x^{22}}\)
Show more


Given ,

\(x^{18}\)

=\((x^2)^9\)

The best answer is B.
User avatar
Abhishek009
User avatar
Board of Directors
Joined: 11 Jun 2011
Last visit: 17 Dec 2025
Posts: 5,903
Own Kudos:
5,454
 [1]
Given Kudos: 463
Status:QA & VA Forum Moderator
Location: India
GPA: 3.5
WE:Business Development (Commercial Banking)
Posts: 5,903
Kudos: 5,454
 [1]
Which of the following is equal to x^18 for all positive values of x ? 08 Oct 2018, 09:29
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
Which of the following is equal to \(x^{18}\) for all positive values of x ?


A. \(x^9 + x^9\)

B. \((x^2)^9\)

C. \((x^9)^9\)

D. \((x^3)^{15}\)

E. \(\frac{x^4}{x^{22}}\)
Show more
Certainly (B) for the reasons cited by the users above.
User avatar
Kinshook
User avatar
Major Poster
Joined: 03 Jun 2019
Last visit: 24 Apr 2026
Posts: 5,986
Own Kudos:
5,859
 [4]
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: 5,986
Kudos: 5,859
 [4]
Which of the following is equal to x^18 for all positive values of x ? 29 Aug 2019, 19:50
1
Kudos
Add Kudos
3
Bookmarks
Bookmark this Post
Bunuel
Which of the following is equal to \(x^{18}\) for all positive values of x ?


A. \(x^9 + x^9\)

B. \((x^2)^9\)

C. \((x^9)^9\)

D. \((x^3)^{15}\)

E. \(\frac{x^4}{x^{22}}\)
Show more

Asked: Which of the following is equal to \(x^{18}\) for all positive values of x ?


A. \(x^9 + x^9\)
2x^9
B. \((x^2)^9\)
x^18
C. \((x^9)^9\)
x^81
D. \((x^3)^{15}\)
x^45
E. \(\frac{x^4}{x^{22}}\)
x^{-18}

IMO B

Posted from my mobile device
User avatar
ScottTargetTestPrep
User avatar
Target Test Prep Representative
Joined: 14 Oct 2015
Last visit: 24 Apr 2026
Posts: 22,285
Own Kudos:
26,534
Given Kudos: 302
Status:Founder & CEO
Affiliations: Target Test Prep
Location: United States (CA)
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 22,285
Kudos: 26,534
Which of the following is equal to x^18 for all positive values of x ? 10 Nov 2020, 07:26
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
Which of the following is equal to \(x^{18}\) for all positive values of x ?


A. \(x^9 + x^9\)

B. \((x^2)^9\)

C. \((x^9)^9\)

D. \((x^3)^{15}\)

E. \(\frac{x^4}{x^{22}}\)
Show more

Solution:

Since (x^2)^9 = x^(2 * 9) = x^18, choice B is the correct answer.

Answer: B
User avatar
ThatDudeKnows
User avatar
Joined: 11 May 2022
Last visit: 27 Jun 2024
Posts: 1,070
Own Kudos:
1,030
Given Kudos: 79
Expert
Expert reply
Posts: 1,070
Kudos: 1,030
Which of the following is equal to x^18 for all positive values of x ? 16 Jul 2022, 15:20
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
Which of the following is equal to \(x^{18}\) for all positive values of x ?


A. \(x^9 + x^9\)

B. \((x^2)^9\)

C. \((x^9)^9\)

D. \((x^3)^{15}\)

E. \(\frac{x^4}{x^{22}}\)
Show more

This is certainly an easy one IF you know your exponents rules (WHICH YOU SHOULD!!!). But let's say you totally blank out on the actual test and forget the rules. You can still get this one right by figuring out the rule using a simpler example. Instead of \(x^{18}\), just do something like \(2^{6}\) and see if you can figure out what's up.

x=2

\(2^{4} = 64\)

We can see in the answer choices that there are some 9's. That's half of the 18 from the question stem. We replaced the 18 with a 6, so every time there's a 9 in an answer choice, we need to replace it with half of 6, so 3.

A. \(2^3 + 2^3 = 8+8 = 16\) ... Nope.

B. \((2^2)^3 = 4^3 = 64\) ... Keep it.

C. \((2^3)^3 = 6^3\) ... 6^3 can't be equal to 4^3 and 4^3 worked, so 6^3 can't. Nope.

D. \((2^3)^{15}\) ... Woah. Huge. Nope.

E. \(\frac{2^4}{2^{22}}\) ... Less than 1? Nope.

Answer choice B.
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,972
Own Kudos:
1,117
Posts: 38,972
Kudos: 1,117
Which of the following is equal to x^18 for all positive values of x ? 30 Nov 2025, 11:57
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
109814 posts
Krunaal
Tuck School Moderator
853 posts