The probability of not drawing a green marble would be 19/23.
If you add together all of the marbles, you get the total number of marbles as 23. This then allows you to write the probability of drawing a green marble as 4/23.
To find the probability of not drawing a green marble, we can then subtract 4/23 from 23/23, as we want the probability of everything except green. 23 - 4 = 19, so 19/23 is the answer.
I hope this helps!
