Source: Official Guide for the GMAT 13th Ed. Problem Solving; #199 Official Guide for the GMAT 2015 14th Ed. Problem Solving; #199
Delia Wang
You could also express each fraction as a subtraction of some small number from 1, giving you - 10001/100010000 + 30009/100030000 = 3/10000 - 1/10000 = 2/10000.
Jun 11, 2017 • Comment
Mike McGarry, Magoosh Tutor
Dec 28, 2013 • Comment
Sergey Volchematiev
You could have used the same trick of the squares difference in the second fraction as well.
Nov 2, 2014 • Reply
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