Please could you help me out with this problem?
Thank you.
The thin conveyor belt
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 GMATGuruNY
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Last edited by GMATGuruNY on Mon Nov 16, 2015 8:28 pm, edited 1 time in total.
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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 15pi. Then C would be the answer. Meaning that it represents the distance between the centers.
Why this is not the case?
Thanks.
 Jim@StratusPrep
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1/2 pi is used because each is 1/2 of a circle with a diameter of 1.
didieravoaka
1) it would have to be A + B + 2C = 15
2) should make sense from #1
didieravoaka
1) it would have to be A + B + 2C = 15
2) should make sense from #1
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