It is currently 21 Feb 2018, 15:13

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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

What is the greatest value y for which 4^y is a factor of 12!?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 43853
What is the greatest value y for which 4^y is a factor of 12!? [#permalink]

Show Tags

New post 29 Jan 2018, 23:11
Expert's post
3
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

42% (00:21) correct 58% (00:36) wrong based on 44 sessions

HideShow timer Statistics

Senior Manager
Senior Manager
User avatar
G
Joined: 17 Oct 2016
Posts: 327
Location: India
Concentration: Operations, Strategy
GPA: 3.73
WE: Design (Real Estate)
GMAT ToolKit User Premium Member CAT Tests
Re: What is the greatest value y for which 4^y is a factor of 12!? [#permalink]

Show Tags

New post 29 Jan 2018, 23:17
D

2^(2*y) is factor of 12!

There are 10 2s in 12! Hence five 4s.


Sent from my iPhone using GMAT Club Forum
_________________

Help with kudos if u found the post useful. Thanks

1 KUDOS received
Manager
Manager
avatar
B
Joined: 15 Oct 2017
Posts: 69
CAT Tests
Re: What is the greatest value y for which 4^y is a factor of 12!? [#permalink]

Show Tags

New post 29 Jan 2018, 23:57
1
This post received
KUDOS
D

4^5 is the biggest factor in terms of 4^y of 12!. Therefore, y's maximum value can be 5.
Expert Post
1 KUDOS received
Target Test Prep Representative
User avatar
G
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 2192
Location: United States (CA)
Re: What is the greatest value y for which 4^y is a factor of 12!? [#permalink]

Show Tags

New post 31 Jan 2018, 16:09
1
This post received
KUDOS
Expert's post
Bunuel wrote:
What is the greatest value y for which 4^y is a factor of 12!?

A. 2
B. 3
C. 4
D. 5
E. 6


Let’s first determine the number of 2’s in 12!.

To determine the number of 2s within 12!, we can use the following shortcut in which we divide 12 by 2, then divide the quotient of 12/2 by 2 and continue this process until we no longer get a nonzero quotient.

12/2 = 6

6/2 = 3

3/2 = 1 (we can ignore the remainder)

Since 1/2 does not produce a nonzero quotient, we can stop.

The next step is to add up our quotients; that sum represents the number of factors of 2 within 12!.

6 + 3 + 1 = 10

We see that there are ten 2’s in 12!; however, since 4 = 2^2, and since 10/2 = 5, we see that there are five 4’s in 12!.

Answer: D
_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Re: What is the greatest value y for which 4^y is a factor of 12!?   [#permalink] 31 Jan 2018, 16:09
Display posts from previous: Sort by

What is the greatest value y for which 4^y is a factor of 12!?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.