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Intern
Joined: 28 May 2010
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In a local school district, the high school and middle
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05 Jul 2010, 12:42
Question Stats:
70% (02:00) correct 30% (02:11) wrong based on 224 sessions
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In a local school district, the high school and middle school each received r dollars toward funding for the student arts program. The high school enrolled 300 students and the middle school enrolled 200 students. Later, the middle school transferred s dollars to the high school so that they would have received the same funding per student. Which of the following is equivalent to s? A. r/2 B. r/3 C. r/4 D. r/5 E. r/6  How I originally did it:
High school: $r, 300 students Middle: $r, 200 students X= amount transfer per student
let R = 600 H: 600/300 + X = 600/300 X 2X = $3/student  $2/student 2X = $1/student X = $0.5/student
therefore, Middle school transfers: S=(0.5)(200) = 100 dollars to High School. Check: H:700/300students = $2.5/student M:500/200students = $2.5/student
so, S=100dollars=R=600/6=100. But that's not the answer!! ah, please help.
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Manager
Joined: 04 Feb 2010
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Re: 700800 PS...simple algebra actually
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05 Jul 2010, 13:34
I set up the equation as such.
(r  s) / 200 = (r + s) / 300
s leaving one school, s entering one school, hence the equation. Dividing the amount of money after the transfer by the number of students.
This gives us:
r / 200  r / 300 = s / 300 + s / 200
100 r / 600 = 500 s / 600
1/6 r = 5/6 s
s = 1/5 r
Hence D.



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Re: 700800 PS...simple algebra actually
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05 Jul 2010, 13:45
Oooops, sorry, algebra mode. Check the solution. 700/500 <> 2.5 700/500 = 2.33333. You forgot to divide the X  the amount transferred  by the number of students. The amount transferred must be 120  for $2.4 per student.



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Re: 700800 PS...simple algebra actually
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05 Jul 2010, 14:19
yeah this problem can be difficult if you don't understand what the problem is asking. it took me a few minutes just to figure out exactly what the problem wanted. once i understood the problem, the algebra was very easy.
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Re: 700800 PS...simple algebra actually
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05 Jul 2010, 14:45
RGM wrote: Oooops, sorry, algebra mode. Check the solution. 700/500 <> 2.5 700/500 = 2.33333. You forgot to divide the X  the amount transferred  by the number of students. The amount transferred must be 120  for $2.4 per student. RGM, I'm so sorry, I can't believe I still don't understand... why am I dividing 700/500? where is 700 from? X is the amount transferred per student, so it's = $0.5/student, so Middle should transfer $0.5/student to High. Since Middle has 200 students, it transfers $100=s to High.... but again, that's wrong, and again, I don't see why it's wrong.



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Re: 700800 PS...simple algebra actually
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05 Jul 2010, 15:07
No worries.
Your calculations used this: ( r / 200 )  s = ( r / 300 ) + s
when it should have used this: ( r  s ) / 200 = ( r + s ) / 300
See the difference. You set R as 600. 600/300 = $2 and 600/200 = $3
So you reasoned that amount to be transferred per student should be $3  $2 = $1. Divide by 2, and get $0.5. $0.5 per student. That's wrong. It is because the transfer isn't divided by the number of students  as such, it's lopsided again, and the amount of money per student isn't equal for both schools. Also the $3  $2 = $1 approach is wrong since you're combining per student dollar amounts that don't have the same number of students (mixing 200 and 300 students).
Case in point. You got the $100 from $0.5*200. Why not $0.5*300? to get the amount of transfer?
You got the 700 by adding the 100 to the 600 original amount. 700 is to be shared by 300 students. the 500 is from 600 minus 100. 500 to be shared by 200 students. The amounts are not equal.
Hope this helps.



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Re: 700800 PS...simple algebra actually
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05 Jul 2010, 16:37
RGM wrote: No worries.
Your calculations used this: ( r / 200 )  s = ( r / 300 ) + s
when it should have used this: ( r  s ) / 200 = ( r + s ) / 300
See the difference. You set R as 600. 600/300 = $2 and 600/200 = $3
So you reasoned that amount to be transferred per student should be $3  $2 = $1. Divide by 2, and get $0.5. $0.5 per student. That's wrong. It is because the transfer isn't divided by the number of students  as such, it's lopsided again, and the amount of money per student isn't equal for both schools. Also the $3  $2 = $1 approach is wrong since you're combining per student dollar amounts that don't have the same number of students (mixing 200 and 300 students).
Case in point. You got the $100 from $0.5*200. Why not $0.5*300? to get the amount of transfer?
You got the 700 by adding the 100 to the 600 original amount. 700 is to be shared by 300 students. the 500 is from 600 minus 100. 500 to be shared by 200 students. The amounts are not equal.
Hope this helps. THANK YOU SO MUCH RGM. lol, that was stupid. 700/300 doesn't equal 2.5, it equals 2.333, so the result doesn't even equal. you're the best.



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Re: 700800 PS...simple algebra actually
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05 Jul 2010, 20:01
knabi wrote: RGM wrote: No worries.
Your calculations used this: ( r / 200 )  s = ( r / 300 ) + s
when it should have used this: ( r  s ) / 200 = ( r + s ) / 300
See the difference. You set R as 600. 600/300 = $2 and 600/200 = $3
So you reasoned that amount to be transferred per student should be $3  $2 = $1. Divide by 2, and get $0.5. $0.5 per student. That's wrong. It is because the transfer isn't divided by the number of students  as such, it's lopsided again, and the amount of money per student isn't equal for both schools. Also the $3  $2 = $1 approach is wrong since you're combining per student dollar amounts that don't have the same number of students (mixing 200 and 300 students).
Case in point. You got the $100 from $0.5*200. Why not $0.5*300? to get the amount of transfer?
You got the 700 by adding the 100 to the 600 original amount. 700 is to be shared by 300 students. the 500 is from 600 minus 100. 500 to be shared by 200 students. The amounts are not equal.
Hope this helps. THANK YOU SO MUCH RGM. lol, that was stupid. 700/300 doesn't equal 2.5, it equals 2.333, so the result doesn't even equal. you're the best. Sure thing. Nah, it's not stupid  we simply just don't see our mistakes from time to time, happens to the best of us.



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Re: 700800 PS...simple algebra actually
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07 Jul 2010, 16:52
I did this the same way as RGM at first, but after reading knabi's attempted solution, I actually think you were on track for a simpler method. You just didn't quite nail it.
if r = $600, then the total cash given is $1,200 ($600 to school A, $600 to school B) and the total students are 500 (200 at A, 300 at B). So for $/student to be the same, it has to be $1200 / 500 students = $2.40/student. School A has $600/200 = $3/student, so they need to give away s = $0.60 for each of their 200 students, or $3/5 * 200.
Thus s = 3/5 * 200 = 600/5 = r/5
Either method is fine, but I thought I'd share this in case it's helpful.



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Re: 700800 PS...simple algebra actually
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10 Jul 2010, 08:09
The way i solved it:
Total per head = 2r/500
After s transfer both schools have total for head. So at High School it will be:
r+s = (300)* (2r/500) = 6r/5 i.e. s = r/5



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Re: 700800 PS...simple algebra actually
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16 Jul 2010, 01:32
how i go about is let R =600 (because of 300, 200 i choose R=600) :
Lets S is fiven by middle school : 600+s /300 = 600s /200 5s = 600 s = 120 (600/5)
This show S= r/5
Answer is D



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Re: 700800 PS...simple algebra actually
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27 Jul 2010, 14:44
I think you may be overcomplicating it.
If they get the same amount of funding per student in the end, then the first school will have 60% and the 2nd school will have 40% of the total funding (300 vs 200).
They start with 50% each. So, 2nd school has to transfer 10% of the total to the first school...which is 1/5 of the initial amount they got.



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Re: 700800 PS...simple algebra actually
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15 Oct 2010, 08:01
this is simpl..just use basic maths.. (rs)/200 = (r+s)/300 s=r/5



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Re: 700800 PS...simple algebra actually
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15 Jun 2011, 23:44
300(rs) = 200(r+s) r = 5s



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Re: In a local school district, the high school and middle
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17 Nov 2013, 04:47
plug smart numbers: H got $250 (r) M got $250 (r) S= $50 H+S=$250+$50=$300 MS=$250$50=$200 now H+S has $1 per 1 student, and HS has $1 per 1 student. S=$50, r=$250 Check with answers: r/5=$250/5=$50



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Re: In a local school district, the high school and middle
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21 Mar 2018, 19:59
Hi All, This is a great question to TEST VALUES. The prompt tells us there are 500 total students. Later on, we're told that money has to move transferred, so that the end result is the same funding PER student. Let's TEST $1 per student.... 500 students $1 each $500 total The question further states that the two schools each received $R each, so each school received the same amount. That means… R = $250 So, the High School got $250 for 300 students and the Middle School got $250 for 200 students Later, the middle school transferred $S to the High School to make the average $1 per student, so the Middle School would have transferred $50 S = $50 Now, the High School has $300 for 300 students and the Middle School has $200 for 200 students Thus, we're looking for an answer that equals 50 when R=250. There's only one answer that matches.. Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: In a local school district, the high school and middle &nbs
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21 Mar 2018, 19:59






