Kaplan CR- Experts Please help

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Kaplan CR- Experts Please help

by rahulvsd » Wed Aug 17, 2011 7:09 am
It takes 4 weeks for a team of 5 professional Window Washers working regular full time hours to completely clean every window of the Empire State building. The building's owner demands that all the windows always be clean.Yet even if the 5 washers work consistently throughout their regular work week,they will not be able to finish cleaning all the windows before some windows will need cleaning .

Which of the following statements as must be true on the basis of the statements above ?


A) If an empire state building window is to be kept clean, it must be cleaned by a professional cleaner.
B)The owner's demand for proper cleaning of all the windows will never be fulfilled.
C) If a team of 5 window washers cleans all the empire state building's windows in less than 4 weeks, some windows will not be properly cleaned.
D) In order to ensure that all of the Empire State Building's windows are clean, the owner must have his window washers work overtime.
E)Some Empire State Building windows must be cleaned more frequently than once every four weeks if they are to be kept clean.
OA: E. I am not so convinced with Kaplan's explanation. Why cant C be a better answer. Experts please help.
Source: — Critical Reasoning |

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by e-GMAT » Wed Aug 17, 2011 1:04 pm
This is a must be true question type, which means that you need to choose the answer type that can be proven true from the information in the passage. Usually an answer for a must be true passage is based on a premise or a combination of premises.

Choice E: Choice E is about windows. It is based on the first and last line of the argument. The last line states that
"even if the 5 washers work consistently throughout their regular work week, they will not be able to finish cleaning all the windows before some windows will need cleaning" This implies that some windows need to be cleaned more frequently.
When you combine this information with the information in the first line (which implies that it takes 4 weeks to clean all the windows) It can be inferred that at least some windows will need cleaning more frequently than once every 4 weeks.

Choice C: Choice C talks about the quality of work, something that we cannot infer about from the passage. It states that if the cleaners finish their work in less than 4 weeks then they will not clean the windows properly. This cannot be implied from the passage since cleaners take 4 weeks if they work their regular hours. There is a chance that the cleaners may be able to clean windows properly and yet finish the work in less than 4 weeks if they work overtime. Moreover, there is no indication in the passage that implies that their (Cleaner's) quality of work may be impacted if they rush through their work.

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by rahulvsd » Thu Aug 18, 2011 7:20 am
Thanks a lot Payal.

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by Ozlemg » Thu Aug 18, 2011 8:26 am
rahulvsd wrote:Thanks a lot Payal.
My 2 cents :

One common mistake for must-be true questions!: Bringing outside experience or information!
Never do this and never ever bring outside info, forget what you know about Empire state, cleaning, window cleaning, how long does it take etc etc, just stay within the context!

Choices that talk about something else that never mentioned in the argumnet or the ones that use strong language can directly be left out!

Cheers!
The more you suffer before the test, the less you will do so in the test! :)