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Re: Last Friday each of the pets at a certain veterinary clinic was given
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05 Jan 2015, 21:35
Hi All,
It looks like everyone is keen on the correct answer, but I do want to point out that viksingh15's explanation does the math incorrectly.
The prompt tells us that last Friday, EACH PET received either 1 or 2 treats. We're asked for the total number of treats that were given out last Friday.
Fact 1: The total number of pets was 90.
Here, we have a minimum and maximum number of treats that could have been given out.
If each pet received 1 treat, then 90(1) = 90 treats would have been given out.
If each pet received 2 treats, then 90(2) = 180 treats would have been given out.
Every integer from 90 to 180, inclusive is a potential answer based on this information.
Fact 1 is INSUFFICIENT.
Fact 2: 2/3 of the pets were given 2 treats each.
This tells us that the total number of pets MUST be a multiple of 3, but doesn't give us an actual number to work with, so there's no way to figure out the total number of treats.
Fact 2 is INSUFFICIENT
Combined, we know...
90 total pets
90(2/3) received 2 treats each = 60(2) = 120 treats
90(1/3) received 1 treat each = 30(1) = 30 treats
Total treats given out = 120 + 30 = 150 treats
These last math "steps" are unnecessary in this question, but there will be questions on the GMAT that require perfect math. In PS questions, it's common enough for one (or more) of the wrong answers to be based on a math mistake or "misread" on the part of the Test Taker, so the proper attention to detail is warranted.
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