There is a blue yellow and green cube in a bag. There are twice as many blue cubes then yellow and there a 4 times as many green balls then yellow

Question

What is the probability I pick out yellow 

Answer 1

Let's assume there is 1 yellow cube in the bag. Because there are 2X as many blue cubes that means there are 2 blue cubes. Because there are 4X as many green cubes (I believe cubes not balls) then that means there are 4 green cubes.

Therefore:

                 1y + 2b + 4g = 7 total cubes

The probability that you pick out the yellow cube in 1 try would be #y/total amt = 1/7.

 Your answer is 1/7.