Bunuel wrote:
Of the following, the closest approximation of \(\sqrt{\frac{12.45*20.12}{99.71}}\) is
Rounding off, the root is roughly equal to
\(\sqrt{\frac{12.5*20}{100}} = \sqrt{\frac{25*10}{100}} = \sqrt{2.5} \)
and that is approximately 1.6 (since 1.6^2 = 2.56). So the answer would have to be 2 here, but it's a bit strange that we have one answer (0.5) that suggests we're meant to find an approximation to the tenths place, but then the right answer is instead rounded off to the nearest integer (and really isn't very close to the value we're asked to approximate). In similar real GMAT questions, I've always found the natural approximation to be very close to the right answer.
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