Since 39 out of 40 marbles are green, the probability of randomly choosing green is 39/40.
However, the probability becomes 100% when you look into the bag and choose a green marble. (Unless you are blind or unable to distinguish blue from green, in which case the probability remains 39/40.)
-3+11p first you add 1+2p that gets you -3 then you do 9p-4 and you get 11p from there you can either solve it, or leave it as is, depending on what your teacher wants.
