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mjfsutherland
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A certain business produced x rakes each month ...

by mjfsutherland Wed Mar 03, 2010 5:28 pm

As I cant seem to find this problem on the forum anywhere else I am guessing I have missed something very obvious, but when I try to solve it, it gets more complicated than I would expect from a GMAT question. There is obviously a much simpler solution.

A certain business produced x rakes each month from November through February and shipped x/2 rakes at the beginning of each month from March through October. The business paid no storage costs for the rakes from November through February, but it paid storage costs of $0.10 per rake each month from March through October for the rakes that had not been shipped. In terms of x, what was the total storage cost, in dollars, that the business paid for the rakes for the 12 months from November through October?

a) 0.40x
b) 1.20x
c) 1.40x
d) 1.60x
e) 3.20x

OA=c

Thanks
luc2r4
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Re: A certain business produced x rakes each month ...

by luc2r4 Fri Mar 05, 2010 12:01 am

Do you know the OA ?
mjfsutherland
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Re: A certain business produced x rakes each month ...

by mjfsutherland Mon Mar 08, 2010 6:39 pm

Sorry I put the OA in white. You can highlight the text to see the answer.

The OA = C
rajkapoor
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Re: A certain business produced x rakes each month ...

by rajkapoor Tue Mar 09, 2010 12:12 am

total rakes produced fro Nov- feb = 4x

cost of storage for month of march =(4x - x/2) * 0.10 (we subtract x/2 one time)
cost of storage for month of april = (4x -x/2-x/2)*0.10 - (we subtract x/2 two times )

cost for each month can be captured with this - 4x - ( x/2 * n ) where n is from 1 to 8
for march , n = 1 , for april , n = 2, october = 8

therefore total storage cost = [(4x -x/2) + (4x - x/2*2) + ........ + (4x - x/2*8)]*0.10
rest is just calculation

total = [4x*8 - x/2(1+2.... + 8)]*0.10
= [32x - x/2*(4.5*8)] * 0.10
= [32x - 18x] * 0.10
=14x * 0.10x
= 1.40x
i ask so i can answer / i answer so i can learn
sandydiwan
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Re: A certain business produced x rakes each month ...

by sandydiwan Wed Mar 10, 2010 2:01 pm

mjfsutherland Wrote:As I cant seem to find this problem on the forum anywhere else I am guessing I have missed something very obvious, but when I try to solve it, it gets more complicated than I would expect from a GMAT question. There is obviously a much simpler solution.

A certain business produced x rakes each month from November through February and shipped x/2 rakes at the beginning of each month from March through October. The business paid no storage costs for the rakes from November through February, but it paid storage costs of $0.10 per rake each month from March through October for the rakes that had not been shipped. In terms of x, what was the total storage cost, in dollars, that the business paid for the rakes for the 12 months from November through October?

a) 0.40x
b) 1.20x
c) 1.40x
d) 1.60x
e) 3.20x

OA=c

Thanks


I solved this within two minutes by using the following approach

Since the question involves x and x/2 , to make calculations easier I took x = 2

So total number of rakes produced from Nov - Feb = 2 * 4 = 8
Storage costs for 8 months between Mar and Oct = .1*(7+6+5+4+3+2+1) = 2.8

From the answer choices , multiple each of them by x = 2 to get 2.8 and only c gives the desired result
Andrew.Skoller
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Re: A certain business produced x rakes each month ...

by Andrew.Skoller Fri Mar 12, 2010 11:44 am

I did the same thing, but used 10 instead of 2, so the I didn't have to plug in at the end. I ended up just getting cost = 14, so it was clear that was 1.4x
mschwrtz
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Re: A certain business produced x rakes each month ...

by mschwrtz Tue Mar 30, 2010 4:25 pm

Nice work. I'll add just one point: the reason that picking a value for x works so neatly is that x shows up not just in the question but also in each of the answer choices. In other words, this is what we call a VIC (Variables in Answer Choices) question.