GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 19 May 2019, 06:05

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

For an integer n = 2^16 * 3^13 * 5^5 * 7^5 * 11^3, what is the value o

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Manager
Manager
avatar
G
Joined: 02 Jun 2015
Posts: 190
Location: Ghana
For an integer n = 2^16 * 3^13 * 5^5 * 7^5 * 11^3, what is the value o  [#permalink]

Show Tags

New post 25 Jul 2017, 11:19
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

50% (00:47) correct 50% (01:13) wrong based on 6 sessions

HideShow timer Statistics

For an integer n = 2^16 * 3^13 * 5^5 * 7^5 * 11^3, what is the value of the first non-zero digit from the right?

A) 1
B) 2
C) 4
D) 6
E) 8

--== Message from the GMAT Club Team ==--

THERE IS LIKELY A BETTER DISCUSSION OF THIS EXACT QUESTION.
This discussion does not meet community quality standards. It has been retired.


If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.

_________________
Kindly press kudos if you find my post helpful
GMAT Tutor
avatar
S
Joined: 24 Jun 2008
Posts: 1511
Re: For an integer n = 2^16 * 3^13 * 5^5 * 7^5 * 11^3, what is the value o  [#permalink]

Show Tags

New post 25 Jul 2017, 11:37
2
Take out the 10s (the 2*5 pairs) and we have:

n = 2^5 * 5^5 * 2^11 * 3^13 * 7^5 * 11^3
n = 10^5 * ( 2^11 * 3^13 * 7^5 * 11^3 )

All the zeros at the end of the number come from the 10^5. The first nonzero digit (from the right) will be the units digit of the number in brackets. So this is now a units digits problem. The units digit of 11^3 is '1', the units digit of 7^5 is 7, the units digit of 3^13 is '3', and the units digit of 2^11 is '8' (anyone unsure how I found those should review units digits and exponents). Multiplying just these units digits, we get

1*7*3*8

which ends in 8.

--== Message from the GMAT Club Team ==--

THERE IS LIKELY A BETTER DISCUSSION OF THIS EXACT QUESTION.
This discussion does not meet community quality standards. It has been retired.


If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.

_________________
GMAT Tutor in Toronto

If you are looking for online GMAT math tutoring, or if you are interested in buying my advanced Quant books and problem sets, please contact me at ianstewartgmat at gmail.com
GMAT Club Bot
Re: For an integer n = 2^16 * 3^13 * 5^5 * 7^5 * 11^3, what is the value o   [#permalink] 25 Jul 2017, 11:37
Display posts from previous: Sort by

For an integer n = 2^16 * 3^13 * 5^5 * 7^5 * 11^3, what is the value o

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


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| 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®.