187,189) Find the value!

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by sanjana » Fri Oct 09, 2009 2:38 am
213) IMO : X/Y

From the given system :

x^2=wy
y^2=xz

Hence,
x^2/y^2 = wy/xz
Reducing, W/Z= X/Y

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by xcusemeplz2009 » Fri Oct 09, 2009 2:47 am
sanjana wrote:213) IMO : X/Y

From the given system :

x^2=wy
y^2=xz

Hence,
x^2/y^2 = wy/xz
Reducing, W/Z= X/Y


reducing will result x^3/y^3
It does not matter how many times you get knocked down , but how many times you get up

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by sanjana » Fri Oct 09, 2009 3:31 am
Sorry...Mistake in cross multiplication!
it is x^3/y^3

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Re: 187,189) Find the value!

by NikolayZ » Fri Oct 09, 2009 8:16 am
ern5231 wrote:212. Abcd is a four integer, ac + bc + ad + bd = 65, | a + bcd | =?

213 W / x = x / y = y / z, then w / z =?
Hey !

212: ac,bc,ad,bd and bcd are 2 and 3 digit integers ? or multiplying a by b and so on ?

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by ern5231 » Sat Oct 10, 2009 8:59 am
OA w^3/x^3

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by xcusemeplz2009 » Sat Oct 10, 2009 9:15 am
ern5231 wrote:OA w^3/x^3
yeah its all same w^3/x^3 or x^3/y^3 or y^3/z^3
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Re: 187,189) Find the value!

by Stuart@KaplanGMAT » Sat Oct 10, 2009 10:10 am
ern5231 wrote:212. Abcd is a four integer, ac + bc + ad + bd = 65, | a + bcd | =?
We need more information to answer this question (or at least some clarification).

I assume that the first part should read:

"Abcd is a four digit integer".

However, we need to know if ac is a two-digit integer or if it's the product of a and c (i.e. a*c), which is normally what it would represent. We need similar clarification for bc, ad, bd and bcd.

When you post questions, please take the time to type them out carefully so that we have all necessary information.

I'm also not sure why a + bcd is in absolute value form; since a, b, c and d are digits, they're by definition positive.

Finally, please always provide the answer choices and the source of the question; had you done so, we probably could have reverse engineered it and figured out how it was supposed to read. Further, understanding how to use answer choices effectively is essential to GMAT success.
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by mehravikas » Sat Oct 10, 2009 4:42 pm
Can you explain how is it same? I am confused.
xcusemeplz2009 wrote:
ern5231 wrote:OA w^3/x^3
yeah its all same w^3/x^3 or x^3/y^3 or y^3/z^3

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by nithi_mystics » Sat Oct 10, 2009 8:08 pm
mehravikas wrote:Can you explain how is it same? I am confused.
xcusemeplz2009 wrote:
ern5231 wrote:OA w^3/x^3
yeah its all same w^3/x^3 or x^3/y^3 or y^3/z^3
When a/b = c/d,
(a/b)^n = (c/d)^n

For example,
take a=4, b=2, c=6 and d=3

4/2 = 6/3 and you can substitute any value for n to check if 4^n/2^n = 6^n/3^n
2^n is always equal to 2^n :)
Thanks
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by mehravikas » Sun Oct 11, 2009 12:14 pm
Ok got it now...basically the answer is to confuse people :-)

but x^3/y^3 is same as w^3/x^3
nithi_mystics wrote:
mehravikas wrote:Can you explain how is it same? I am confused.
xcusemeplz2009 wrote:
ern5231 wrote:OA w^3/x^3
yeah its all same w^3/x^3 or x^3/y^3 or y^3/z^3
When a/b = c/d,
(a/b)^n = (c/d)^n

For example,
take a=4, b=2, c=6 and d=3

4/2 = 6/3 and you can substitute any value for n to check if 4^n/2^n = 6^n/3^n
2^n is always equal to 2^n :)