Question

There are only blue cubes, yellow cubes and green cubes in a bag.

Answer 1

Let the yellow cubes be x

yellow = x
blue = 2x                // Blue cubes is twice of yellow
Green = 8x              // Green is four times of blue

Ratio:
Yellow : Blue : Green
   1       :   2    :     8

P(Yellow) = 1/11

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Answer: The probability of getting a yellow cube is 1/11.
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