GMAT Problem Solving (PS) | Re: A certain telescope X increases the visual range of a particular locat

Telescope X: 90 + 180 = 270. So, increase = 200%.
Telescope Y: 45 + 135 = 180. So, increase = 300%.

Percentage increase in Y is more than percentage increase in X by 300-200/200 = 50%. Ans - B.

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