Comparing Ratio

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by anshumishra » Sat Dec 25, 2010 1:41 pm
gmat7202011 wrote:What could be a faster way to find out which one is greater

173/212 or 181/225

Thank You
173*225 > 181*212

So, 173/212 > 181/212

Or

0.81 > 0.80

Some times multiplication takes less time as compared to decimal representation. But it can vary based on the data set provided.
Thanks
Anshu

(Every mistake is a lesson learned )

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by anshumishra » Sat Dec 25, 2010 1:51 pm
Another observation :

181/225 ~= 160/200 (I could represent it easily as I know 25*9 = 225 and 25*8 = 200, so numerator in the same ratio becomes, almost equal to 160)
The second fraction : 173/212

212 is almost equal to average of 200 and 225

So,
181/225 ~= 160/200 ~= 171/212 (average of numerator and denominator)

Now, clearly the second fraction : 173/212 is greater than 171/212 (or 181/225).

Hope that helps !
Thanks
Anshu

(Every mistake is a lesson learned )