Answer:
have a good day/night may i please have a branllist
Explanation:
1/3
There is 21 marbles and if you divided by 3 it gets 7.
7/21 is equal to 1/3
Therefore the possibility of picking a blue marble is 1/3.
there are an equal amount of all three colors of marbles in the bag, so the probability of selecting a blue marble is just 1/3.