The thin conveyor belt

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The thin conveyor belt

by didieravoaka » Mon Nov 16, 2015 8:01 pm
Please could you help me out with this problem?

Thank you.


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by GMATGuruNY » Mon Nov 16, 2015 8:22 pm
Last edited by GMATGuruNY on Mon Nov 16, 2015 8:28 pm, edited 1 time in total.
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by didieravoaka » Mon Nov 16, 2015 8:57 pm
GMATGuruNY wrote:Image

Thank you Mitch, this is very helpful.
But I still have two questions:
1. Why the belt isn't equal to A+B+C instead of A+B+C+D since C=D?
2. Why C is not equal to 15-pi. Then C would be the answer. Meaning that it represents the distance between the centers.

Why this is not the case?


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by jain2016 » Mon Nov 16, 2015 11:29 pm
Hi Mitch ,

Why did you do A=1/2 pie. Please explain.

Also is there any other approach for this question?

Please advise.

Many thanks in advance.


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by Jim@StratusPrep » Tue Nov 17, 2015 8:43 am
1/2 pi is used because each is 1/2 of a circle with a diameter of 1.


1) it would have to be A + B + 2C = 15
2) should make sense from #1
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