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

It is currently 17 Jan 2019, 22:03

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 in January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
  • The winning strategy for a high GRE score

     January 17, 2019

     January 17, 2019

     08:00 AM PST

     09:00 AM PST

    Learn the winning strategy for a high GRE score — what do people who reach a high score do differently? We're going to share insights, tips and strategies from data we've collected from over 50,000 students who used examPAL.
  • Free GMAT Strategy Webinar

     January 19, 2019

     January 19, 2019

     07:00 AM PST

     09:00 AM PST

    Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.

A farmer constructs a fence along the northern edge of his property

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

Hide Tags

 
Manager
Manager
avatar
B
Joined: 13 Sep 2016
Posts: 121
A farmer constructs a fence along the northern edge of his property  [#permalink]

Show Tags

New post 03 Oct 2016, 05:27
1
7
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

61% (01:12) correct 39% (01:21) wrong based on 273 sessions

HideShow timer Statistics

A farmer constructs a fence along the northern edge of his property, using materials such that he places a post every 7 meters. if he uses 100 posts, how many meters will the fence span?

A. 686
B. 693
C. 700
D. 707
E. 770
Intern
Intern
avatar
Joined: 20 Sep 2016
Posts: 2
GMAT ToolKit User
Re: A farmer constructs a fence along the northern edge of his property  [#permalink]

Show Tags

New post 03 Oct 2016, 06:26
1
1
Between two post there is one length of fencing material, between three post there are two lengths, thus between 100 posts there are 99 lengths..
99 x 7 = 693

[url=http://gmatclub.com/forum/gmat-toolkit-iphone-ipod-application-82830.html][img]http://gmatclub.com/static/posted_from.png[/img][/url] [size=85][i][color=#666666]Posted from[/color] [b][url=http://gmatclub.com/forum/gmat-toolkit-iphone-ipod-application-82830.html][color=#459926]GMAT ToolKit[/color][/url][/b][/i][/size]
CEO
CEO
User avatar
D
Joined: 11 Sep 2015
Posts: 3331
Location: Canada
Re: A farmer constructs a fence along the northern edge of his property  [#permalink]

Show Tags

New post 03 Oct 2016, 06:32
3
Top Contributor
alanforde800Maximus wrote:
A farmer constructs a fence along the northern edge of his property, using materials such
that he places a post every 7 meters. if he uses 100 posts, how many meters will the fence span?

a)686
b)693
c)700
d)707
e)770

Please assist with above problem.


Let's look for a pattern...

1 post: fence span = 0 meters
2 posts: fence span = 7 meters
3 posts: fence span = 7 + 7 = 14 meters
4 posts: fence span = 7 + 7 + 7 = 21 meters
5 posts: fence span = 7 + 7 + 7 + 7 = 28 meters
.
.
.
We can see that, for n posts, we add 7 n-1 times
.
.
.
100 posts: fence span = sum of 99 sevens = (99)(7) = 693 meters
Answer:

RELATED VIDEO

_________________

Test confidently with gmatprepnow.com
Image

Manager
Manager
User avatar
S
Joined: 22 Nov 2016
Posts: 208
Location: United States
Concentration: Leadership, Strategy
GPA: 3.4
Reviews Badge
Re: A farmer constructs a fence along the northern edge of his property  [#permalink]

Show Tags

New post 01 Jul 2017, 14:59
1
|--7mts--|--7mts--|..............

He places a fence after each post. I.e he builds 99 fences before putting down the 100th post.
99*7
Units digit is 3. No need to calculate. Answer is B
_________________

Kudosity killed the cat but your kudos can save it.

Senior SC Moderator
avatar
V
Joined: 22 May 2016
Posts: 2344
Re: A farmer constructs a fence along the northern edge of his property  [#permalink]

Show Tags

New post 02 Jul 2017, 15:23
alanforde800Maximus wrote:
A farmer constructs a fence along the northern edge of his property, using materials such
that he places a post every 7 meters. if he uses 100 posts, how many meters will the fence span?

a)686
b)693
c)700
d)707
e)770

Please assist with above problem.

I like the solutions above. I literally drew a picture.

For any specific range with "marked off" beginning and end values, there will always be one more tick than interval.

Wasn't sure I remembered that rule correctly, so I drew 10 posts, and wrote 7 in between:

|7|7|7|7|7|7|7|7|7|

Then I counted. 10 fence posts, but only 9 lengths of 7 in between. So 100 fence posts = 99 intervals of 7 meters.

99*7 = 693. Answer B
_________________

Never look down on anybody unless you're helping them up.
--Jesse Jackson

EMPOWERgmat Instructor
User avatar
V
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 13341
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170
Re: A farmer constructs a fence along the northern edge of his property  [#permalink]

Show Tags

New post 23 Jan 2018, 13:23
Hi All,

This is an example of a 'fence post' problem (literally and figuratively). The 'key' to these types of questions is to remember that there's a 'first post' that you have to include in your total. Here's a much simpler example of this type of math - if you read pages 2 through 5 (inclusive) of a book, then how many pages did you read? It's 4 pages (not 3), since you read pages 2, 3, 4 and 5.

Thus, we have the first post, then another post every 7 meters. That means that we're 99(7) meters away from the first post once we plant the last post.

(99)(7) = 693

Final Answer:

GMAT assassins aren't born, they're made,
Rich
_________________

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests Free
  Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

*****Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!*****

GMAT Club Bot
Re: A farmer constructs a fence along the northern edge of his property &nbs [#permalink] 23 Jan 2018, 13:23
Display posts from previous: Sort by

A farmer constructs a fence along the northern edge of his property

  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®.