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

It is currently 23 May 2013, 21:05
Customize  |  Hide

How much did a certain call cost? 1) The call lasted 53

  Question banks Downloads My Bookmarks Reviews  
Author Message
TAGS:
Director
Director
Joined: 23 May 2008
Posts: 842
Followers: 3

Kudos [?]: 19 [0], given: 0

GMAT Tests User
How much did a certain call cost? 1) The call lasted 53 [#permalink] New post 26 Apr 2009, 13:27
00:00

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
How much did a certain call cost?

1) The call lasted 53 minutes

2) The cost for the first 3 minutes was 5 times the cost for each additional minute

This is an easy problem, but there is something wrong with the logic I used to approach this problem. Can someone help me troubleshoot?

correct way:

let c=cost for first 3 minutes

c + c/5(50min)= total cost

i initially approacehed the problem like this:

let c =cost

5c (3min) + c(50min) = total cost

why is this wrong?


thanks!
SVP
SVP
Joined: 17 Jun 2008
Posts: 1593
Followers: 7

Kudos [?]: 131 [0], given: 0

GMAT Tests User
Re: #73 OG DS [#permalink] New post 28 Apr 2009, 02:10
bigtreezl wrote:
How much did a certain call cost?

1) The call lasted 53 minutes

2) The cost for the first 3 minutes was 5 times the cost for each additional minute

This is an easy problem, but there is something wrong with the logic I used to approach this problem. Can someone help me troubleshoot?

correct way:

let c=cost for first 3 minutes

c + c/5(50min)= total cost

i initially approacehed the problem like this:

let c =cost

5c (3min) + c(50min) = total cost

why is this wrong?


thanks!


For the highlited line, if C is the cost of each additional minute beyond 3 minutes, then the total cost should be
5C + C(50) = 55C

and not 5C * 3 + c * 50 as 5C is the cost of first three minutes.
Director
Director
Joined: 23 May 2008
Posts: 842
Followers: 3

Kudos [?]: 19 [0], given: 0

GMAT Tests User
Re: #73 OG DS [#permalink] New post 28 Apr 2009, 09:23
scthakur wrote:
bigtreezl wrote:
How much did a certain call cost?

1) The call lasted 53 minutes

2) The cost for the first 3 minutes was 5 times the cost for each additional minute

This is an easy problem, but there is something wrong with the logic I used to approach this problem. Can someone help me troubleshoot?

correct way:

let c=cost for first 3 minutes

c + c/5(50min)= total cost

i initially approacehed the problem like this:

let c =cost

5c (3min) + c(50min) = total cost

why is this wrong?


thanks!


For the highlited line, if C is the cost of each additional minute beyond 3 minutes, then the total cost should be
5C + C(50) = 55C

and not 5C * 3 + c * 50 as 5C is the cost of first three minutes.



Ok thanks!

I guess i was thinking the price per minute for the first three minutes, but the question stem doesnt say that...
Manager
Manager
Joined: 11 Apr 2009
Posts: 170
Followers: 2

Kudos [?]: 13 [0], given: 5

Re: #73 OG DS [#permalink] New post 28 Apr 2009, 15:34
5c (3min) + c(50min) = total cost. Even with this equation, we do need c in order to find the cost of the call. Hence, E.
Director
Director
Joined: 23 May 2008
Posts: 842
Followers: 3

Kudos [?]: 19 [0], given: 0

GMAT Tests User
Re: #73 OG DS [#permalink] New post 28 Apr 2009, 16:16
typhoidX wrote:
How was the original worded? You wouldn't need to do all that calculation if they don't give you some kind of per-minute rate, since the answer would be E no matter what algebra you do, right?


yeah true..but i am taking a different approach this time in doing all of the math problems in OG. Answers are kind of irrelevant, I'm more interested in theory, set up, structure and technique. Basically I'm looking for new ways to think about the problems that I already did.
Re: #73 OG DS   [#permalink] 28 Apr 2009, 16:16
    Similar topics Author Replies Last post
Similar
Topics:
New posts How much studying did you do the last 4 days? zakk 5 05 Sep 2007, 22:29
New posts How much did you improve your last 3 weeks of prep? MeddlingKid 6 29 Apr 2008, 07:45
Popular new posts How much $$$ did/will this application season cost you? domtri33 39 10 Feb 2009, 14:11
New posts EXPERTS_POSTS_IN_THIS_TOPIC cost of a call gettinit 6 21 Nov 2010, 20:46
New posts How much did school actually cost? mappleby 0 18 Oct 2011, 07:54
Display posts from previous: Sort by

How much did a certain call cost? 1) The call lasted 53

  Question banks Downloads My Bookmarks Reviews  


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®.