Answer:
55% probability of getting a purple marble if you take a marble out of the bag
Explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
In this question, we have that:
20 marbles.
6 are red.
3 are green
The rest(x) are purple.
So
6 + 3 + x = 20
x = 11
20 marbles, of which 11 are purple.
11/20 = 0.55
55% probability of getting a purple marble if you take a marble out of the bag