Question 1155507
2 ways to do this with equal probability 9/20*3/19 RG 
3/20*9/19 GR
That is 54/380 or 27/190 =0.142

BB is 8/20*7/19=56/380 or 14./95=0.147

Find probability both are blue which is 0.147.  So at least 1 that is not blue is everything else or 0.853

if first marble is green, there are 19 left, 2 of which are green, so the probability is 2/19=0.105