GMAT preptest question

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GMAT preptest question

by awilhelm » Sun Dec 14, 2008 8:41 pm
If m, r, x and y are positive numbers, is the ratio of m to r equal to the ratio of x to y?

1) The ratio of m to y is equal to the ratio of x to r
2) The ratio of m + x to r + y is equal to the ratio of x + y

Help please!
Source: — Data Sufficiency |

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Re: GMAT preptest question

by tritrantran » Sun Dec 14, 2008 9:28 pm
awilhelm wrote:If m, r, x and y are positive numbers, is the ratio of m to r equal to the ratio of x to y?

1) The ratio of m to y is equal to the ratio of x to r
2) The ratio of m + x to r + y is equal to the ratio of x + y

Help please!
So it's asking if (m/r) = (x/y)
cross multiply, is (my) = (rx) ?

St (1)
(m/y) = (x/y)
m = x

If m = x, then y = r, and my=rx SUFFICIENT

St (2)
The ratio of m + x to r + y is equal to the ratio of x + y

(m+x)/(r+y) = (x+y)
you'll have a y^2 term and can't get it in the form my=rx

INSUFFICIENT

IMO A

what's the OA?

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by awilhelm » Sun Dec 14, 2008 9:38 pm
OA is B!

I'm confused...it's from a preptest question so there's no explanation...

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Re: GMAT preptest question

by vittalgmat » Sun Dec 14, 2008 10:09 pm
tritrantran wrote:
awilhelm wrote:If m, r, x and y are positive numbers, is the ratio of m to r equal to the ratio of x to y?

1) The ratio of m to y is equal to the ratio of x to r
2) The ratio of m + x to r + y is equal to the ratio of x + y

Help please!
So it's asking if (m/r) = (x/y)
cross multiply, is (my) = (rx) ?

St (1)
(m/y) = (x/y)
m = x

tritrantran,
there is a typo in your stmt1: it should be
m/y = x/r.
So it stmt1 is insufficient.

i am still trying to figure out how the OA is B.
Can u pls verify the question??

thanks

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by tritrantran » Sun Dec 14, 2008 10:15 pm
You're right, thanks for catching that. I can't figure out Statement (2) either.

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by mental » Sun Dec 14, 2008 10:39 pm
If m, r, x and y are positive numbers, is the ratio of m to r equal to the ratio of x to y?

1) The ratio of m to y is equal to the ratio of x to r
2) The ratio of m + x to r + y is equal to the ratio of x + y
There seems to an error in statement 2

As Vittal explained about statement 1: Insufficient

Statement 2: I suppose the question was "The ratio of m + x to r + y is equal to the ratio of x to y

(m+x)/(r+y) = x/y
y(m+x) = x(r+y).....................cross-multiply
my + xy = xr + xy
my = xr..........................xy cancelled from both sides
B Sufficient

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Re: GMAT preptest question

by scoobydooby » Sun Dec 14, 2008 10:41 pm
awilhelm wrote:If m, r, x and y are positive numbers, is the ratio of m to r equal to the ratio of x to y?

1) The ratio of m to y is equal to the ratio of x to r
2) The ratio of m + x to r + y is equal to the ratio of x + y

Help please!

agree with mental

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by awilhelm » Mon Dec 15, 2008 10:20 am
Mental is correct. I wrote statement 2 incorrectly. Sorry about that!!! Thanks for clearing that up.