Answer: 5/51
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Step-by-step explanation:
We have 6 green out of 6+6+6 = 18 total
The probability of getting green is 6/18 = 1/3.
After selecting that green jelly bean and not putting it back, we have 6-1 = 5 green out of 18-1 = 17 total.
The probability of selecting another green is 5/17.
Multiply the two fractions 1/3 and 5/17
(1/3)*(5/17) = (1*5)/(3*17) = 5/51
The probability of selecting two greens in a row is 5/51 where we do not put the first selection back. We also do not replace the green jelly bean with some other identical copy.
Note: 5/51 = 0.098039 approximately