Cost per unit for the housing project?

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If the total cost of a housing project with f units is $1,750,000, what was the cost per unit for the housing project?

(1) If half as many units were built for the same total price, the cost per unit would be $250,000.
(2) If six more units had been built for the same total price, the cost per unit would be $3,750 less.

Why is A not sufficient?
Source: — Data Sufficiency |

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by ajith » Sun Jan 31, 2010 2:54 am
bhumika.k.shah wrote:If the total cost of a housing project with f units is $1,750,000, what was the cost per unit for the housing project?

(1) If half as many units were built for the same total price, the cost per unit would be $250,000.
(2) If six more units had been built for the same total price, the cost per unit would be $3,750 less.

Why is A not sufficient?
Avg cost per unit = Total cost / number of units

Let n be the number of units

1) 1,750,000/(n/2) = 250000
=> 1,750,000/n = 125,000

Sufficient

2) 1750000/(n+6) =1,750,000/n - 3750

1 Equation 1 variable solvable

Sufficient

So each is sufficient
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by bhumika.k.shah » Sun Jan 31, 2010 2:57 am
thats what i thought

but thats not correct !!

i did the same calculation but its not correct !!!

:-(
ajith wrote:
bhumika.k.shah wrote:If the total cost of a housing project with f units is $1,750,000, what was the cost per unit for the housing project?

(1) If half as many units were built for the same total price, the cost per unit would be $250,000.
(2) If six more units had been built for the same total price, the cost per unit would be $3,750 less.

Why is A not sufficient?
Avg cost per unit = Total cost / number of units

Let n be the number of units

1) 1,750,000/(n/2) = 250000
=> 1,750,000/n = 125,000

Sufficient

2) 1750000/(n+6) =1,750,000/n - 3750

1 Equation 1 variable solvable

Sufficient

So each is sufficient

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by h_jitendras » Sun Jan 31, 2010 3:44 am
OA pls?


bhumika.k.shah wrote:thats what i thought

but thats not correct !!

i did the same calculation but its not correct !!!

:-(
ajith wrote:
bhumika.k.shah wrote:If the total cost of a housing project with f units is $1,750,000, what was the cost per unit for the housing project?

(1) If half as many units were built for the same total price, the cost per unit would be $250,000.
(2) If six more units had been built for the same total price, the cost per unit would be $3,750 less.

Why is A not sufficient?
Avg cost per unit = Total cost / number of units

Let n be the number of units

1) 1,750,000/(n/2) = 250000
=> 1,750,000/n = 125,000

Sufficient

2) 1750000/(n+6) =1,750,000/n - 3750

1 Equation 1 variable solvable

Sufficient

So each is sufficient

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by ajith » Sun Jan 31, 2010 4:07 am
OA & OE please in that case
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by bhumika.k.shah » Sun Jan 31, 2010 10:58 am
Statement 2 alone is also sufficient, since it allows you to write the equation 1750000/f-3750=1750000/f+6 . From this, you could calculate the value of f, and hence, the cost per unit for the housing project.

OA B

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by ajith » Sun Jan 31, 2010 11:02 am
bhumika.k.shah wrote:Statement 2 alone is also sufficient, since it allows you to write the equation 1750000/f-3750=1750000/f+6 . From this, you could calculate the value of f, and hence, the cost per unit for the housing project.

OA B
What about statement 1; it is also sufficient .. OA is wrong.. which book is it?
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by bhumika.k.shah » Sun Jan 31, 2010 11:05 am
It ain't from any book ;-)

But the OA is B
ajith wrote:
bhumika.k.shah wrote:Statement 2 alone is also sufficient, since it allows you to write the equation 1750000/f-3750=1750000/f+6 . From this, you could calculate the value of f, and hence, the cost per unit for the housing project.

OA B
What about statement 1; it is also sufficient .. OA is wrong.. which book is it?

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by ajith » Sun Jan 31, 2010 11:10 am
bhumika.k.shah wrote:It ain't from any book ;-)

But the OA is B
I insist you to reveal the source :)
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by bhumika.k.shah » Sun Jan 31, 2010 11:16 am
sowree dude can't ;)

ajith wrote:
bhumika.k.shah wrote:It ain't from any book ;-)

But the OA is B
I insist you to reveal the source :)

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by ajith » Sun Jan 31, 2010 11:18 am
bhumika.k.shah wrote:sowree dude can't ;)

ajith wrote:
bhumika.k.shah wrote:It ain't from any book ;-)

But the OA is B
I insist you to reveal the source :)
Well then Lets agree to disagree
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by money9111 » Sun Jan 31, 2010 8:55 pm
i never understand why people say they can't reveal a source. lol what's the secret if you're posting all of the questions anyway?
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by bhumika.k.shah » Mon Feb 01, 2010 3:36 am
Thanks! :-P
money9111 wrote:i never understand why people say they can't reveal a source. lol what's the secret if you're posting all of the questions anyway?

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by ajith » Mon Feb 01, 2010 3:40 am
bhumika.k.shah wrote:Thanks! :-P
money9111 wrote:i never understand why people say they can't reveal a source. lol what's the secret if you're posting all of the questions anyway?
That doesn't make sense, or does it?
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by bhumika.k.shah » Mon Feb 01, 2010 3:44 am
sense the tone of the author :-P
ajith wrote:
bhumika.k.shah wrote:Thanks! :-P
money9111 wrote:i never understand why people say they can't reveal a source. lol what's the secret if you're posting all of the questions anyway?
That doesn't make sense, or does it?