Jun 29 07:00 AM PDT  09:00 AM PDT Learn reading strategies that can help even nonvoracious reader to master GMAT RC Jun 30 07:00 AM PDT  09:00 AM PDT Get personalized insights on how to achieve your Target Quant Score. Jul 01 08:00 AM PDT  09:00 AM PDT Game of Timers is a teambased competition based on solving GMAT questions to win epic prizes! Starting July 1st, compete to win prep materials while studying for GMAT! Registration is Open! Jul 01 10:00 PM PDT  11:00 PM PDT Join a FREE 1day workshop and learn how to ace the GMAT while keeping your fulltime job. Limited for the first 99 registrants.
Author 
Message 
TAGS:

Hide Tags

Manager
Joined: 19 Dec 2007
Posts: 75

A certain college has a studenttoteacher ratio of 11 to 1.
[#permalink]
Show Tags
Updated on: 12 Sep 2013, 07:52
Question Stats:
87% (01:46) correct 13% (02:08) wrong based on 201 sessions
HideShow timer Statistics
A certain college has a studenttoteacher ratio of 11 to 1. The average (arithmetic mean) annual salary for teachers is $26,000. If the college pays a total of $3,380,000 in annual salaries to its teachers, how many students does the college have ? (A) 130 (B) 169 (C) 1,300 (D) 1,430 (E) 1,560 Hi, this is a pretty easy question, I know. Still, It took me a bit more than 3 min to perform all the calculation.. Are there any tips on how to calculate everything quicker? In general, I will greatly appreciate if anyone can share any ideas on how to do calculations quickly.. Calculations of fractionsdecimals or just large numbers take my time. moreover I just tend to make careless mistakes here being pressed on time.......Please, advise.. Thanks much
Official Answer and Stats are available only to registered users. Register/ Login.
Originally posted by chica on 27 Jan 2008, 10:39.
Last edited by Bunuel on 12 Sep 2013, 07:52, edited 1 time in total.
Edited the question and added the OA.



CEO
Joined: 17 Nov 2007
Posts: 3382
Concentration: Entrepreneurship, Other
Schools: Chicago (Booth)  Class of 2011

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
27 Jan 2008, 10:52
I don't know faster way than this one:
Attachments
t59131.gif [ 2.88 KiB  Viewed 7568 times ]
_________________
HOT! GMAT TOOLKIT 2 (iOS) / GMAT TOOLKIT (Android)  The OFFICIAL GMAT CLUB PREP APP, a musthave app especially if you aim at 700+  Limited GMAT/GRE Math tutoring in Chicago



VP
Joined: 28 Dec 2005
Posts: 1400

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
27 Jan 2008, 16:07
i agree, i cant see a 'fast' way.
first step is to figure out how many total teachers there are, which is possible as you know the average salary and total salary
average = sum/total > 26,000 = 3,380,000 / total > total =130
students/teachers = 11/1 > 11/1 = x/130 where x=# of students > x=130*11



Director
Joined: 01 May 2007
Posts: 751

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
27 Jan 2008, 16:45
Agree.. Just need to sharpen your basic math skills. Dividing 3380000/26000 should actually calculate out pretty fast when you cancel out some zeros.



SVP
Joined: 29 Mar 2007
Posts: 2325

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
27 Jan 2008, 16:56
I agree as well. Just gunna have to do some calculations.
3380000/26000 > 130 then just 130*11 =1430.



SVP
Joined: 29 Aug 2007
Posts: 2258

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
27 Jan 2008, 19:58
chica wrote: A certain college has a studenttoteacher ratio of 11 to 1. The average (arithmetic mean) annual salary for teachers is $26,000. If the college pays a total of $3,380,000 in annual salaries to its teachers, how many students does the college have ? (A) 130 (B) 169 (C) 1,300 (D) 1,430 (E) 1,560 Hi, this is a pretty easy question, I know. Still, It took me a bit more than 3 min to perform all the calculation.. Are there any tips on how to calculate everything quicker? In general, I will greatly appreciate if anyone can share any ideas on how to do calculations quickly.. Calculations of fractionsdecimals or just large numbers take my time. moreover I just tend to make careless mistakes here being pressed on time.......Please, advise.. Thanks much no . of student = (11) ($3,380,000 / $26,000) = 11 (3380 / 26) = 11 (1649 / 13) = 11 (130) = 1,430 reducing numerator and denomenator would be sometime easy.
_________________
Verbal: http://gmatclub.com/forum/newtotheverbalforumpleasereadthisfirst77546.html Math: http://gmatclub.com/forum/newtothemathforumpleasereadthisfirst77764.html Gmat: http://gmatclub.com/forum/everythingyouneedtoprepareforthegmatrevised77983.html
GT



Intern
Joined: 06 Feb 2013
Posts: 48

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
12 Sep 2013, 05:47
Could someone show me a purely algebraic approach. I can't connect those elements (two equations). I solve fast via the common sense, but I it looks like I am doing something silly on the proportions side. I have this ready, after taking out three 0's, \(26t = 3800\) (after 3800/t=26), and then since we have \(11t=s\) it must be that \(\frac{s}{11}=\frac{t}{1}\)? But then, if it is true, I am confused with my common sense...please help me untangle myself. How do you express ratios as stated in the problem?
_________________
There are times when I do not mind kudos...I do enjoy giving some for help



Manager
Joined: 04 Apr 2013
Posts: 118

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
12 Sep 2013, 06:19
obs23 wrote: Could someone show me a purely algebraic approach. I can't connect those elements (two equations). I solve fast via the common sense, but I it looks like I am doing something silly on the proportions side.
I have this ready, after taking out three 0's, \(26t = 3800\) (after 3800/t=26), and then since we have \(11t=s\) it must be that \(\frac{s}{11}=\frac{t}{1}\)? But then, if it is true, I am confused with my common sense...please help me untangle myself. How do you express ratios as stated in the problem? chica, This calculation is v easy if you know 13^2 = 169. 3380000/ 26000 = 3380/26 = 1690/13 = 130
_________________
Maadhu
MGMAT1  540 ( Trying to improve )



Intern
Joined: 06 Feb 2013
Posts: 48

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
12 Sep 2013, 06:53
Quote: chica,
This calculation is v easy if you know 13^2 = 169.
3380000/ 26000 = 3380/26 = 1690/13 = 130 Dude, I appreciate your effort, but I am not looking for a solution, I am looking for a specific way to solve, the one I need to get a grasp of. Thanks.
_________________
There are times when I do not mind kudos...I do enjoy giving some for help



Intern
Joined: 30 Aug 2013
Posts: 2

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
12 Sep 2013, 07:33
obs23 wrote: Could someone show me a purely algebraic approach. I can't connect those elements (two equations). I solve fast via the common sense, but I it looks like I am doing something silly on the proportions side.
I have this ready, after taking out three 0's, \(26t = 3800\) (after 3800/t=26), and then since we have \(11t=s\) it must be that \(\frac{s}{11}=\frac{t}{1}\)? But then, if it is true, I am confused with my common sense...please help me untangle myself. How do you express ratios as stated in the problem? This is an arithmetic question, using algebra and adding variables only makes this problem complicated. Additionally, you shouldn't be concerned about expressing the solution in ratios if that doesn't appear as an answer form. But regarding your equation. Your math is correct s/11 = t/1 (This is confirmed through backsolving with the arithmetic... 1430/11 = 130/1) But this proportion doesn't actually give you the answer to the problem since there are two unsolved variables, so I'm not sure what use it is.



Veritas Prep GMAT Instructor
Joined: 11 Dec 2012
Posts: 312

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
12 Sep 2013, 07:39
obs23 wrote: Could someone show me a purely algebraic approach. I can't connect those elements (two equations). I solve fast via the common sense, but I it looks like I am doing something silly on the proportions side.
I have this ready, after taking out three 0's, \(26t = 3800\) (after 3800/t=26), and then since we have \(11t=s\) it must be that \(\frac{s}{11}=\frac{t}{1}\)? But then, if it is true, I am confused with my common sense...please help me untangle myself. How do you express ratios as stated in the problem? Hi obs, if you're intent on solving the question through ratios, then you can, but it's not necessarily the best approach. That being said, let's attack it as a ratio problem. Firstly, there's a slight typo in how you copied the math, it's actually \(26t = 3,380\). You can then figure out that whatever t is, if you multiply it by 11 you'll get the number of students. So yes \(\frac{s}{11}=\frac{t}{1}\), and you already have \(26t = 3,380\) so \(t= \frac{3,380}{26}\). Now solve t for 130, and then \(11t=s\). s is 1430. A sneakier way to solve this: The GMAT will always try and trap you, so if it asks for the number of students (s), the number of teachers (t) will also be a trap answer somewhere on the list. If you recognize this, then all you have to do is look for the two answer choices that are 11 away from one another. The bigger one will be the answer and the smaller will be the trap. This kind of "fourth wall" shortcut isn't for everyone, but it can be very helpful when crunched for time or unsure about the math. Hope this helps! Ron
_________________



Intern
Joined: 06 Feb 2013
Posts: 48

Re: PS: Please, advise on how to calculate quicker!!!
[#permalink]
Show Tags
14 Sep 2013, 02:19
VeritasPrepRon wrote: obs23 wrote: Could someone show me a purely algebraic approach. I can't connect those elements (two equations). I solve fast via the common sense, but I it looks like I am doing something silly on the proportions side.
I have this ready, after taking out three 0's, \(26t = 3800\) (after 3800/t=26), and then since we have \(11t=s\) it must be that \(\frac{s}{11}=\frac{t}{1}\)? But then, if it is true, I am confused with my common sense...please help me untangle myself. How do you express ratios as stated in the problem? Hi obs, if you're intent on solving the question through ratios, then you can, but it's not necessarily the best approach. That being said, let's attack it as a ratio problem. Firstly, there's a slight typo in how you copied the math, it's actually \(26t = 3,380\). You can then figure out that whatever t is, if you multiply it by 11 you'll get the number of students. So yes \(\frac{s}{11}=\frac{t}{1}\), and you already have \(26t = 3,380\) so \(t= \frac{3,380}{26}\). Now solve t for 130, and then \(11t=s\). s is 1430. A sneakier way to solve this: The GMAT will always try and trap you, so if it asks for the number of students (s), the number of teachers (t) will also be a trap answer somewhere on the list. If you recognize this, then all you have to do is look for the two answer choices that are 11 away from one another. The bigger one will be the answer and the smaller will be the trap. This kind of "fourth wall" shortcut isn't for everyone, but it can be very helpful when crunched for time or unsure about the math. Hope this helps! Ron Thanks Ron, all makes sense. As for the use, I was just a bit rusty on ratios so I wanted to make sure I do the simple stuff correctly in algebraic terms.
_________________
There are times when I do not mind kudos...I do enjoy giving some for help



Veritas Prep GMAT Instructor
Joined: 11 Dec 2012
Posts: 312

Re: A certain college has a studenttoteacher ratio of 11 to 1.
[#permalink]
Show Tags
14 Sep 2013, 07:58
No problem obs23, as mentioned it may not be the most obvious way to solve this problem, but I like to remind students that pretty much any GMAT math problem can be solved in a variety of ways. If you have one way to solve the problem, you're probably okay, but if you have three different ways, then you're definitely in great shape to solve any variation of the problem on test day. Hope this makes sense! Ron
_________________



Intern
Joined: 26 Apr 2017
Posts: 9

Re: A certain college has a studenttoteacher ratio of 11 to 1.
[#permalink]
Show Tags
27 Oct 2018, 11:37
Easy 13^2 = 169. 3380000/ 26000 = 3380/26 = 1690/13 = 130




Re: A certain college has a studenttoteacher ratio of 11 to 1.
[#permalink]
27 Oct 2018, 11:37






