Find all School-related info fast with the new School-Specific MBA Forum

It is currently 20 Oct 2014, 23:15

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If each term in the sum A1 + A2 + .....+ An is either 7 or

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Director
Director
User avatar
Joined: 08 Jun 2007
Posts: 583
Followers: 2

Kudos [?]: 72 [0], given: 0

If each term in the sum A1 + A2 + .....+ An is either 7 or [#permalink] New post 15 Dec 2007, 19:26
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
If each term in the sum A1 + A2 + .....+ An is either 7 or 77 and the sum equals 350
,which of the following could be equal to n ?

A 38
B 39
C 40
D 41
E 42
CEO
CEO
User avatar
Joined: 29 Mar 2007
Posts: 2593
Followers: 16

Kudos [?]: 197 [0], given: 0

Re: PS - GmatPrep [#permalink] New post 15 Dec 2007, 20:58
ashkrs wrote:
If each term in the sum A1 + A2 + .....+ An is either 7 or 77 and the sum equals 350
,which of the following could be equal to n ?

A 38
B 39
C 40
D 41
E 42


I get C.

Took me about 1min 30 sec, but it seems to work...

Just tried values 7*38=266 +77=343 +7

So 39*7 +77=350.

Unless Im missin somethin.
Director
Director
User avatar
Joined: 08 Jun 2007
Posts: 583
Followers: 2

Kudos [?]: 72 [0], given: 0

Re: PS - GmatPrep [#permalink] New post 15 Dec 2007, 21:06
GMATBLACKBELT wrote:
ashkrs wrote:
If each term in the sum A1 + A2 + .....+ An is either 7 or 77 and the sum equals 350
,which of the following could be equal to n ?

A 38
B 39
C 40
D 41
E 42


I get C.

Took me about 1min 30 sec, but it seems to work...

Just tried values 7*38=266 +77=343 +7

So 39*7 +77=350.

Unless Im missin somethin.


no u are not missin anythin....OA is C.
but how did you arrived..on 7*38=266 +77=343 +7

i tried plugging too ..but tool hell lotta time for me to put all combinations ..before i arrived at c ..just wanted to know whats the best way to do this..
Expert Post
CEO
CEO
User avatar
Joined: 17 Nov 2007
Posts: 3571
Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
Followers: 367

Kudos [?]: 1849 [0], given: 358

GMAT ToolKit User Premium Member
 [#permalink] New post 16 Dec 2007, 01:32
Expert's post
C.

other way.

350/7=50 but 50 is out of answer cases.

we add one 77 and exclude eleven 7, so 350=(50-11)*7+1*77 ==> n=50-11+1=40
Manager
Manager
avatar
Joined: 12 Jun 2006
Posts: 55
Followers: 1

Kudos [?]: 5 [0], given: 0

 [#permalink] New post 16 Dec 2007, 23:26
walker wrote:
C.

other way.

350/7=50 but 50 is out of answer cases.

we add one 77 and exclude eleven 7, so 350=(50-11)*7+1*77 ==> n=50-11+1=40
Sorry I didn't understand how you came up with the above equation? Plz elaborate
Expert Post
CEO
CEO
User avatar
Joined: 17 Nov 2007
Posts: 3571
Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
Followers: 367

Kudos [?]: 1849 [0], given: 358

GMAT ToolKit User Premium Member
 [#permalink] New post 16 Dec 2007, 23:40
Expert's post
lonesome307 wrote:
Sorry I didn't understand how you came up with the above equation? Plz elaborate


step 1. we can represent 350 as a sum of only 7. 350=50*7. So, we should sum 50 terms - out of answers.

step 2. we add one 77 and exclude eleven 7 to balance the sum: 350=50*7+1*77-11*7=50*39+1*77. we have 40 terms.

we had gone to the next step if 40 would not be answer.

possible step: add next 77 and exclude eleven 7 to balance question:
350=50*7+2*77-22*7=50*28+2*77. we have 30 terms.
1 KUDOS received
Manager
Manager
avatar
Joined: 03 Sep 2006
Posts: 233
Followers: 1

Kudos [?]: 5 [1] , given: 0

 [#permalink] New post 17 Dec 2007, 00:35
1
This post received
KUDOS
Late, but C:

350 = 7*50 (but we don't have such answer)
350-77 = 273 (and 273/7 = 39), so answer is 40.

walker, nice trick - noted!
  [#permalink] 17 Dec 2007, 00:35
    Similar topics Author Replies Last post
Similar
Topics:
If each term in the sum a1 + a2 +....+ an is either 7 or 77 suhaschan 0 29 Jul 2014, 06:20
2 If each term in the sum A1+A2+ An is either 7 or 77 and the shobuj40 3 01 Jan 2009, 11:49
2 If each term in the sum a1 + a2 + ... + an is either 7 or 77 tarek99 11 29 Sep 2008, 08:45
If each term in the sum a1 + a2,..., + aN is either 7 or 77 raconteur 5 13 Apr 2007, 19:37
If each term in the sum A1+A2+...+ An is either 7 or 77 and sm176811 7 16 Apr 2006, 03:14
Display posts from previous: Sort by

If each term in the sum A1 + A2 + .....+ An is either 7 or

  Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group and phpBB SEO

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®.