There are only blue cubes, yellow cubes and green cubes in a bag.There are twice as many blue cubes as yellow cubes and four times as many green cubes as blue cubes.Hannah takes at random a cube from the bag.work out the probability that Hannah takes a yellow cube. ( 3 marks )( Sorry if this question was already answered but I can't find it. Sorry! >_< )

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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