NEW HERE? LEARN MORE
closeclose
Last visit was: 25 Apr 2024, 10:56 It is currently 25 Apr 2024, 10:56
Decision Tracker
My Rewards
New posts
New comers' posts

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

If a = 125^6*15^4*2048^2, how many digits does a have?

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
User avatar
P
gmatcafe
Manager
Manager
Joined: 27 Sep 2020
Posts: 191
Own Kudos [?]: 195 [12]
Given Kudos: 97
Location: Uzbekistan
Concentration: Finance, Strategy
Schools: Marshall '25 Smeal Carey Ross '25
GPA: 3.73
WE:Consulting (Consulting)
Send PM
If a = 125^6*15^4*2048^2, how many digits does a have? [#permalink] New post   Updated on: 10 Nov 2020, 15:27
12
Bookmarks
00:00
A
B
C
D
E

Difficulty:

55% (hard)

Question Stats:

60% (01:45) correct 40% (02:07) wrong based on 140 sessions
Hide Show timer Statistics
If \(a=125^6*15^4*2048^2\), how many digits does a have?

A) 22
B) 23
C) 24
D) 25
E) 26
ShowHide Answer
Official Answer
C

Originally posted by gmatcafe on 09 Nov 2020, 21:56.
Last edited by Bunuel on 10 Nov 2020, 15:27, edited 2 times in total.
Renamed the topic and edited the question.
User avatar
L
chetan2u
RC & DI Moderator
Joined: 02 Aug 2009
Status:Math and DI Expert
Posts: 11178
Own Kudos [?]: 31925 [4]
Given Kudos: 290
Send PM
Reviews Badge
If a = 125^6*15^4*2048^2, how many digits does a have? [#permalink] New post   09 Nov 2020, 22:05
1
Kudos
3
Bookmarks
Expert Reply
gmatcafe wrote:
If a=\(125^6*15^4*2048^2\), how many digits does a have?
A) 24
B) 26
C) 22
D) 23
E) 25


Let us get all terms in standard form.

a=\(125^6*15^4*2048^2=(5^3)^6*(3*5)^4*(2^{11})^2=5^{(18+4)}*3^4*2^{22}=(2*5)^{22}*3^4=10^{22}*81\)
So 22 Zeroes and 81 as first 2 digits
Total = 24
avatar
B
Yiannisa
Intern
Intern
Joined: 30 Jan 2020
Posts: 2
Own Kudos [?]: 2 [2]
Given Kudos: 3
Location: South Africa
Schools: Said '23 (S)
GPA: 3.9
Send PM
Re: If a = 125^6*15^4*2048^2, how many digits does a have? [#permalink] New post   10 Nov 2020, 09:46
2
Kudos
Where does the 3^6 come from? Is it not 3^4.
Making the total digits 24?
User avatar
B
ZNLove
Intern
Intern
Joined: 19 Jun 2018
Posts: 38
Own Kudos [?]: 6 [1]
Given Kudos: 89
Location: Brazil
Schools: Kellogg '22 (D) Kenan-Flagler '22 (D) McDonough'23 (A) ESADE '22 (A)
GMAT 1: 650 Q44 V35
GPA: 3.5
WE:Analyst (Other)
Send PM
Reviews Badge
Re: If a = 125^6*15^4*2048^2, how many digits does a have? [#permalink] New post   10 Nov 2020, 15:23
1
Kudos
Yiannisa wrote:
Where does the 3^6 come from? Is it not 3^4.
Making the total digits 24?

Exactly!

I think it is C
User avatar
B
Nups1324
Manager
Manager
Joined: 05 Jan 2020
Posts: 108
Own Kudos [?]: 47 [1]
Given Kudos: 353
Send PM
Re: If a = 125^6*15^4*2048^2, how many digits does a have? [#permalink] New post   11 Nov 2020, 03:36
Yiannisa wrote:
Where does the 3^6 come from? Is it not 3^4.
Making the total digits 24?



Where is 3^6? Yiannisa

Posted from my mobile device
User avatar
B
lovesuit
Intern
Intern
Joined: 10 Aug 2023
Posts: 29
Own Kudos [?]: 20 [1]
Given Kudos: 5
Send PM
CAT Tests
If a = 125^6*15^4*2048^2, how many digits does a have? [#permalink] New post   19 Oct 2023, 07:11
1
Kudos
gmatcafe wrote:
If \(a=125^6*15^4*2048^2\), how many digits does a have?

A) 22
B) 23
C) 24
D) 25
E) 26


took me 0.47secs

100^6 * 10^4 * 1000^2
10^12 * 10^4 * 10^8
12+4+8=24
IMO C
note: this method might not work for every question. it depends on the digits
GMAT Club Bot
gmatclubot
If a = 125^6*15^4*2048^2, how many digits does a have? [#permalink]
19 Oct 2023, 07:11
Moderators:
Bunuel
Math Expert
92914 posts
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions