Question 1190821
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If the colors are in the ratio 9:10:11, then there are 9x yellow, 10x blue, and 11x black umbrellas.  The total number of umbrellas is (9 + 10 + 11)x = 30x.


Divide the number of yellow umbrellas by the total number of umbrellas.

																
John
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My calculator said it, I believe it, that settles it
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