What is the ratio of -25 : -20?

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What is the ratio of -25 : -20?

by Reviewer6 » Mon May 23, 2011 1:55 am
What is the ratio of -25 : -20?

Is it 5 : 4 or -5 : -4?

What are the rules for negative ratios?
Should we consider them in DS questions?

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by Geva@EconomistGMAT » Mon May 23, 2011 4:10 am
Reviewer6 wrote:What is the ratio of -25 : -20?

Is it 5 : 4 or -5 : -4?

What are the rules for negative ratios?
Should we consider them in DS questions?
I have not seen this concept tested anywhere in the GMAT, but the answer is "both". The ratio of -5:-4 is the same as the ratio of 5:4: it's the same ratio, expanded (or reduced) by the sane factor on both sides. Your question is the same as asking "what is the ratio of 100:50? Is it 4:2, or 2:1?" the answer is "both - they're all the same ratio".
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by Ian Stewart » Wed Jun 22, 2011 1:31 pm
On the GMAT, ratios will *always* only contain positive quantities, so you don't need to be concerned with what the ratio of -5 to -4 would mean.
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