For today's GMAT Question of the Day, we have an AD/BCE Value Question, relating to question #311 from the Official Guide for GMAT Review, 2017. See below for a clear, step-by-step example and explanation.
We need to find:
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Obviously, we need information about Guy’s gross income and his deductions. Because you’ve already scanned the clues (right?), you know that this is a CE question – clue (1) only mentions gross income, and clue (2) only mentions deductions. So, eliminate A, D, and B
AD/BCE
(1) and (2) Let’s try some examples, and let’s use multiples of $100 to keep calculations simple:
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Note that I only changed the deductions and I didn’t actually calculate the percent change for each example. It’s plain to see that they are not equal.
The correct answer is E.
Takeaways:
- Be on the lookout for CE problems (see 246 and 255 for examples of easy CE problems).
- Don’t create more examples than you need. In this case we only changed the deductions.
- Use multiples of $100 in percent problems that don’t include actual value
- Don’t calculate unless you have to!
John is a Senior MyGuru GMAT tutor based in Chicago, but is also the founder of Owl Test Prep . We encourage you to check out their web-site and YouTube channel.