Source: Revised GRE PDF 1st Ed. Section 5: Math; #4 (p. 72)


A power station is located on the boundary

A power station is located on the boundary of a square region that measures 10 miles on each side. Three substations are located inside the square region. Quantity A : The sum of the distances from the power station to each of the substations Quantity B : 30 miles Quantity A is greater., Quantity B is greater., The two quantities are equal., The relationship cannot be determined from the information given.

3 Explanations


Kara Rattermann

The problem does not say where inside the square region the 3 power stations are located. As such, these 3 power stations could be located where the video implies which would make Quantity A > Quantity B. However, in the same way, these 3 power stations could be located closer to the boundary where the power station is located and thus, Quantity A < Quantity B.

Therefore, D should be the correct answer since the relationship cannot be definitively determined with the given information.

Dec 6, 2019 • Comment

Adam Lyons, Magoosh Tutor

That's exactly right!

Dec 24, 2019 • Reply


Anindita Dey

The question said that the substations are inside the square region not in the boundary. If they are not in the boundary, how can we compare the length of the diagonal of the square with the distance to the substation?

Sep 5, 2018 • Comment

David Recine, Magoosh Tutor

That is a tricky distinction. What's important to remember is that "inside the square," means *anywhere* inside, even in the parts of the square that are very close to the boundary. It's possible that the power stations could even be inside the square but *touching* the boundary. In that case, if the diagonal itself, when multiplied by 3, amounts to a value higher than 30, then three lengths that are only slightly shorter than the diagonal could also add up to more than 30.

Sep 16, 2018 • Reply


Gravatar Chris Lele, Magoosh Tutor

Sep 25, 2012 • Comment

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